docs: screenshots of the Prime Cost Report against restored production data

Rendered from the restored backup, so the figures are a real client's
rather than fixtures — including the weekly view's em dashes, which are
what a fortnightly pay cycle actually looks like through weekly columns.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

docs/2026-08-16-sales-summary-business-impact.html

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+<title>Restaurant Books That Balance</title>
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+<div class="wrap">
+
+<header>
+  <div class="kicker">Sales summaries &middot; measured on a copy of live data</div>
+  <h1>Restaurant Books That Balance</h1>
+  <p class="lede">Every trading day, each restaurant's books should show the money taken and the
+  money earned agreeing to the penny. On roughly one day in sixteen they did not. This is what was
+  wrong, what it was costing, and what the fix is worth &mdash; measured by running the real job over
+  ninety days of real trading.</p>
+  <div class="facts">
+    <span><b>Period</b> 10 May &ndash; 7 Aug 2026</span>
+    <span><b>Restaurants</b> <span class="n">210</span></span>
+    <span><b>Restaurant-days</b> <span class="n">18,900</span></span>
+    <span><b>Nothing live was changed</b></span>
+  </div>
+</header>
+
+<section>
+  <div class="strip">
+    <div>
+      <span class="lbl">Books as they stand</span>
+      <span class="big n">$70,276.50</span>
+      <span class="sub"><span class="n">1,191</span> days that don't balance</span>
+    </div>
+    <div class="mid" aria-hidden="true">&rarr;</div>
+    <div>
+      <span class="lbl">Same period, after the fix</span>
+      <span class="big after n">$2,379.45</span>
+      <span class="sub"><span class="n">122</span> days that don't balance</span>
+    </div>
+  </div>
+
+  <div class="cards">
+    <div class="card ok"><span class="v">1,069</span><span class="k">days brought into balance</span></div>
+    <div class="card ok"><span class="v">0</span><span class="k">days broken by the change</span></div>
+    <div class="card ok"><span class="v">0</span><span class="k">correct days altered</span></div>
+    <div class="card"><span class="v">96.6%</span><span class="k">of the discrepancy removed</span></div>
+  </div>
+
+  <div class="measure">
+    <p>Put plainly: <b>on nine days out of ten that were wrong, the books now close.</b> Of the 122
+    days still open, only 32 are worth more than ten cents &mdash; the rest are till rounding.</p>
+  </div>
+</section>
+
+<section>
+  <h2>What an unbalanced day costs</h2>
+  <div class="measure">
+    <p>A day that does not balance cannot be signed off. Someone has to open it, compare it against
+    the till, and work out which figure is missing &mdash; and until they do, that restaurant's
+    period is not closed.</p>
+    <p>Across these ninety days that was <b>1,191 restaurant-days needing investigation &mdash; about
+    thirteen every single day.</b> After the fix it is 122 across the whole period, and only 32 of
+    those are worth more than ten cents: roughly <b>one day every third day</b> that genuinely needs
+    a human.</p>
+    <p>The second cost is subtler and worse. Where the two records of a duplicated restaurant traded
+    figures between them, the same day could reconcile differently depending on when you looked. That
+    is not a number anyone can defend in a review, and it is the reason R2 is a requirement rather
+    than a nicety.</p>
+  </div>
+  <div class="cards">
+    <div class="card"><span class="v">~13</span><span class="k">restaurant-days a day needing investigation, before</span></div>
+    <div class="card ok"><span class="v">~1.4</span><span class="k">restaurant-days a day, after</span></div>
+    <div class="card ok"><span class="v">90%</span><span class="k">less manual reconciliation</span></div>
+  </div>
+</section>
+
+<section>
+  <h2>What the business needs from this</h2>
+  <div class="measure">
+    <p>Four requirements. Everything below is judged against them.</p>
+  </div>
+  <dl class="req">
+    <dt>R1</dt>
+    <dd><b>A day's books must balance.</b> Money taken must equal money earned, to the penny. A day
+    that doesn't balance can't be signed off, and someone has to work out why by hand.</dd>
+    <dt>R2</dt>
+    <dd><b>Each restaurant's records must stay its own.</b> A payment or refund must belong to one
+    restaurant and stop moving. Figures that change owner between reports can't be reconciled.</dd>
+    <dt>R3</dt>
+    <dd><b>Cancelling an order must not delete another restaurant's money.</b> Removing a voided
+    order should affect that order only.</dd>
+    <dt>R4</dt>
+    <dd><b>When the numbers can't be trusted, that must show.</b> A silently plausible figure is
+    worse than a visibly wrong one.</dd>
+  </dl>
+</section>
+
+<section>
+  <h2>What was going wrong</h2>
+
+  <div class="case">
+    <h4>Two records for one restaurant, fighting over the same money <span class="faint">&mdash; R2, R3</span></h4>
+    <p class="measure">Ten restaurants were set up twice in the system, as two separate customer
+    records, and both were importing from the same till. Because the two records competed for the
+    same payments and refunds, a refund could belong to one record in the morning and the other by
+    the afternoon. Over time this had moved <b>3,387 refunds, 4,069 payouts and 2,628 cash-drawer
+    shifts</b> between records. Nineteen pairs have been affected historically; ten still share a
+    till today.</p>
+    <p class="measure">It also meant a single card payment could be attached to both records' copies
+    of an order. That is the R3 hazard: the nightly job removes orders the till reports as voided,
+    and removing an order removes its payments &mdash; so cancelling one restaurant's order could
+    quietly delete the other's payment. In a sample of 20,000 orders, <b>11,469 payments had two
+    owners.</b></p>
+  </div>
+
+  <div class="case">
+    <h4>Refunded tips still counted as income <span class="faint">&mdash; R1</span></h4>
+    <p class="measure">When a guest was refunded, the tip came back too. The summary kept crediting
+    the original tip, so the day showed income the restaurant no longer had.</p>
+  </div>
+
+  <div class="case">
+    <h4>Service charges collected but never recorded as earned <span class="faint">&mdash; R1</span></h4>
+    <p class="measure">A catering fee or auto-gratuity is charged inside the customer's card payment,
+    so it arrived as money taken &mdash; but nothing recorded it as money earned. Every order
+    carrying one left the day short by exactly that amount. This was the single largest cause.</p>
+  </div>
+
+  <div class="case">
+    <h4>Refunds arriving for restaurants whose sales were never imported <span class="faint">&mdash; R4</span></h4>
+    <p class="measure">A handful of records receive refunds while none of their sales reach the
+    system. Those days cannot balance, because half the transaction is not there. This one is
+    <b>deliberately left visible</b> rather than fixed &mdash; see below.</p>
+  </div>
+</section>
+
+<section>
+  <h2>What the fix is worth</h2>
+  <div class="measure">
+    <p>The real nightly job was run over the same ninety days twice &mdash; once as it behaves today,
+    once with the fixes on &mdash; against the same copy of live data. These are measured outcomes,
+    not estimates.</p>
+  </div>
+  <div class="scroll">
+    <table>
+      <thead><tr><th>Stage</th><th class="r">Days not balancing</th><th class="r">Clean</th><th class="r">Discrepancy</th></tr></thead>
+      <tbody>
+        <tr><td>Books as they stand</td><td class="r">1,191</td><td class="r">93.70%</td><td class="r">$70,276.50</td></tr>
+        <tr><td>Counting refunded tips correctly</td><td class="r">890</td><td class="r">95.29%</td><td class="r">$67,032.09</td></tr>
+        <tr class="sum"><td>Recording service charges as earned</td><td class="r good">122</td><td class="r good">99.35%</td><td class="r good">$2,379.45</td></tr>
+      </tbody>
+    </table>
+  </div>
+  <div class="scroll">
+    <table>
+      <thead><tr><th>Change</th><th class="r">Days fixed</th><th class="r">Days broken</th><th class="r">Correct days altered</th><th class="r">Money involved</th></tr></thead>
+      <tbody>
+        <tr><td>Refunded tips</td><td class="r good">301</td><td class="r good">0</td><td class="r good">0</td><td class="r">$4,027.21</td></tr>
+        <tr><td>Service charges</td><td class="r good">768</td><td class="r good">0</td><td class="r good">0</td><td class="r">$64,752.64</td></tr>
+        <tr class="sum"><td>Both together</td><td class="r good">1,069</td><td class="r good">0</td><td class="r good">0</td><td class="r">$67,897.05</td></tr>
+      </tbody>
+    </table>
+  </div>
+  <div class="note">
+    <span class="h">Nothing that was already right was touched</span>
+    <p>Of 18,900 restaurant-days, <b>17,827 came out identical</b> &mdash; not just still balancing,
+    but line for line the same figures. Every day that changed was already wrong. This was checked at
+    the level of individual lines (category, amount to the cent, and which account it posts to), not
+    just each day's bottom line, because a day can keep balancing while the figures inside it move.</p>
+  </div>
+</section>
+
+<section>
+  <h2>What it looks like on a real day</h2>
+  <div class="measure">
+    <p>Three days from the period. In each case the correction equals the discrepancy exactly &mdash;
+    which is what you would expect if the fix is recording something real that was recorded nowhere.</p>
+  </div>
+
+  <div class="scroll">
+    <table>
+      <thead><tr><th>A catering fee &mdash; NGPA, 4 June</th><th class="r">Before</th><th class="r">After</th></tr></thead>
+      <tbody>
+        <tr class="hl"><td><b>Service charges</b></td><td class="r bad">not recorded</td><td class="r">1,344.86</td></tr>
+        <tr><td class="faint">Card payments</td><td class="r faint">16,914.26</td><td class="r faint">16,914.26</td></tr>
+        <tr class="sum"><td>Day out by</td><td class="r bad">1,344.86</td><td class="r good">0.00</td></tr>
+      </tbody>
+    </table>
+  </div>
+  <p class="measure">The guests paid the catering fee inside their card payments. Nothing in the
+  books said the restaurant had earned it, so the day was short by exactly the fee.</p>
+
+  <div class="scroll">
+    <table>
+      <thead><tr><th>A refunded tip &mdash; NGFL, 19 May</th><th class="r">Before</th><th class="r">After</th></tr></thead>
+      <tbody>
+        <tr class="hl"><td><b>Tips</b></td><td class="r">238.46</td><td class="r">70.42</td></tr>
+        <tr><td class="faint">Card refunds</td><td class="r faint">168.04</td><td class="r faint">168.04</td></tr>
+        <tr class="sum"><td>Day out by</td><td class="r bad">&minus;168.04</td><td class="r good">0.00</td></tr>
+      </tbody>
+    </table>
+  </div>
+  <p class="measure">Guests were refunded $168.04, tips included. The books kept crediting the full
+  original tip. The corrected figure matches the refund to the penny.</p>
+
+  <div class="scroll">
+    <table>
+      <thead><tr><th>One restaurant, two records &mdash; 11 May</th><th class="r">Record A</th><th class="r">Record B</th></tr></thead>
+      <tbody>
+        <tr><td>Orders that day</td><td class="r">221</td><td class="r">221</td></tr>
+        <tr class="hl"><td><b>Refunds that day</b></td><td class="r bad">none</td><td class="r">2 &mdash; $2,232.29</td></tr>
+        <tr class="sum"><td>Day out by</td><td class="r bad">2,232.29</td><td class="r good">0.00</td></tr>
+      </tbody>
+    </table>
+  </div>
+  <p class="measure">The same restaurant, twice in the system. Both records held the same 221 orders,
+  but the refunds existed only once. The record without them showed the sales being returned and no
+  refunds against them, and was out by exactly what its twin was holding. Across its whole history
+  that record held <b>158,535 orders and five refunds.</b></p>
+</section>
+
+<section>
+  <h2>Making the duplicated restaurants whole</h2>
+  <div class="measure">
+    <p>The duplicated restaurants needed more than the arithmetic fixes, and this is the part with a
+    real choice in it.</p>
+    <p>Orders were always recorded per customer record, so both copies of a restaurant built their
+    own order history. Refunds and payouts were not &mdash; only one record ever held each of them.
+    So one copy shows returns with no refunds against them, and the other looks fine.</p>
+    <p><b>Rather than invent duplicate records, the fix asks the till again.</b> Once each record
+    carries its own identity, replaying ninety days of history means each one imports its own copy
+    and the two sets of books converge on their own &mdash; no code inventing figures that someone
+    then has to trust.</p>
+  </div>
+  <div class="cards">
+    <div class="card"><span class="v">423</span><span class="k">days out of balance on these records, before</span></div>
+    <div class="card ok"><span class="v">3</span><span class="k">days out of balance, after</span></div>
+    <div class="card"><span class="v">$18,508</span><span class="k">discrepancy before</span></div>
+    <div class="card ok"><span class="v">$649</span><span class="k">discrepancy after</span></div>
+  </div>
+  <div class="measure">
+    <p>The alternative was to retire one record of each pair. That was measured too, and it is worse:
+    it leaves <b>279 days and $7,790.54</b> open, and it forces a decision about whose trading history
+    to abandon. Replaying instead leaves 122 days and $2,379.45, and no record is lost.</p>
+  </div>
+  <div class="note warn">
+    <span class="h">A capped import, found while doing this</span>
+    <p>The refund import asked the till for a restaurant's refunds and read only the first page of
+    the answer. The till sends a hundred at a time, so any location with more than a hundred refunds
+    silently returned a hundred &mdash; and the response looked complete. <b>This was quietly
+    truncating the nightly refund import for every busy location, not only the duplicated ones.</b>
+    Now fixed.</p>
+  </div>
+</section>
+
+<section>
+  <h2>What is left, and what it is</h2>
+  <div class="scroll">
+    <table>
+      <thead><tr><th>Remaining discrepancy</th><th class="r">Days</th><th class="r">Amount</th></tr></thead>
+      <tbody>
+        <tr><td>Real trading days &mdash; small, mostly rounding</td><td class="r">106</td><td class="r">$1,151.80</td></tr>
+        <tr class="sum"><td>Refunds for restaurants whose sales never arrive</td><td class="r">16</td><td class="r">$1,227.65</td></tr>
+      </tbody>
+    </table>
+  </div>
+  <div class="measure">
+    <p>Of the 106 trading days, only <b>three</b> are on the duplicated restaurants, and all three are
+    understood: two are a day where the till recorded $6,358.99 of card payments against $6,059.57 of
+    orders &mdash; a genuine gap in the till's own figures, not a fault in the books &mdash; and one
+    is an auto-gratuity booked as a service charge. The remaining 103 days come to <b>$502.96 spread
+    across 190 restaurants</b>, mostly a few cents each.</p>
+    <p><b>That $502.96 has been identical every time this was measured</b>, across several rebuilds
+    with deliberately different preparation. It is the floor this work reaches.</p>
+    <p>The 16 remaining days belong to two restaurants &mdash; <span class="mono">NG4S</span> and
+    <span class="mono">NGPS</span> &mdash; that receive refunds while none of their sales are
+    imported. Their books cannot close until the sales arrive. <b>These are deliberately left visibly
+    out of balance (R4).</b> The arithmetic could be made to agree in one line, and that change was
+    written, measured and then removed: an unbalanced day is the only signal anyone gets that a
+    restaurant's sales are missing. Closing it would remove the alarm and leave the fire.</p>
+  </div>
+</section>
+
+<section>
+  <h2>What rollout costs, and what it risks</h2>
+  <div class="scroll">
+    <table>
+      <thead><tr><th>Step</th><th class="r">Cost</th><th>Risk</th></tr></thead>
+      <tbody>
+        <tr><td>Deploy the change</td><td class="r">minutes</td><td>None on its own &mdash; the two accounting changes are off per restaurant by default</td></tr>
+        <tr><td>Re-label existing records</td><td class="r">~38 min</td><td>Runs with imports paused; newest month first, so stopping early is safe</td></tr>
+        <tr><td>Replay 90 days for the 10 duplicated restaurants</td><td class="r">~5.9 hrs</td><td>Overnight job; reads from the till only</td></tr>
+        <tr><td>Recompute the books, then switch on per restaurant</td><td class="r">~25 min</td><td>Reversible &mdash; switching a restaurant back off restores today's behaviour exactly</td></tr>
+      </tbody>
+    </table>
+  </div>
+  <div class="measure">
+    <p>The whole sequence is one overnight maintenance window. No customer record is retired and no
+    trading history is discarded. The accounting changes go on a few restaurants at a time, and
+    switching one back off is the rollback.</p>
+  </div>
+</section>
+
+<section>
+  <h2>Three decisions needed</h2>
+  <dl class="req">
+    <dt>Accounting</dt>
+    <dd><b>Which revenue account service charges post to.</b> Currently <span class="mono">49000
+    Service Income</span>, chosen so the work could be measured. It affects how revenue is reported,
+    never whether a day balances. Needs sign-off before switching any restaurant on.</dd>
+    <dt>Operations</dt>
+    <dd><b>Why <span class="mono">NG4S</span> and <span class="mono">NGPS</span> receive refunds but
+    no sales.</b> 160 refunds worth $4,347.68 predate any order for these restaurants. Replaying
+    their history from the till is the cheap first thing to try &mdash; it is what resolved seven
+    similar cases.</dd>
+    <dt>Reporting</dt>
+    <dd><b>Ten restaurants remain in the system twice, by design.</b> Each copy now keeps complete,
+    correct books. If any report adds figures across customer records, one restaurant's takings would
+    be counted twice at that layer. Worth confirming before this ships.</dd>
+  </dl>
+</section>
+
+<footer>
+  <span>Measured against a restored copy of live data as at 14 Aug 2026, over 10 May &ndash; 7 Aug
+  2026: 210 restaurants, 18,900 restaurant-days. Nothing in the live system was read or written.</span>
+  <span>A day counts as out of balance when money taken minus money earned differs by half a penny or
+  more. Figures were captured directly after each run rather than reconstructed afterwards.</span>
+</footer>
+
+</div>

src/clj/auto_ap/ssr/components/aside.clj

@@ -95,7 +95,7 @@
                     "sales"
                    (#{::payment-routes/all-page ::payment-routes/pending-page ::payment-routes/cleared-page   ::payment-routes/voided-page} (:matched-route request))
                    "payments"
-                   (#{::ledger-routes/all-page ::ledger-routes/external-page ::ledger-routes/external-import-page ::ledger-routes/balance-sheet ::ledger-routes/cash-flows ::ledger-routes/profit-and-loss} (:matched-route request))
+                   (#{::ledger-routes/all-page ::ledger-routes/external-page ::ledger-routes/external-import-page ::ledger-routes/balance-sheet ::ledger-routes/cash-flows ::ledger-routes/profit-and-loss ::ledger-routes/prime-cost} (:matched-route request))
                    "ledger"
                    :else
                    nil)]
@@ -320,6 +320,11 @@
                                                          :profit-and-loss)} "Old profit and loss"))
                    (menu-button- {:href (bidi/path-for client-routes/routes
                                                        :profit-and-loss-detail)} "Profit & Loss Detail")
+                   (menu-button- {:href (bidi/path-for ssr-routes/only-routes
+                                                       ::ledger-routes/prime-cost)
+                                  :active? (= ::ledger-routes/prime-cost (:matched-route request))
+                                  :hx-boost "true"}
+                                 "Prime Cost Report")
                    (menu-button- {:href (bidi/path-for client-routes/routes
                                                        :cash-flows)} "Cash Flows")
                    (if (is-admin? (:identity request))

src/clj/auto_ap/ssr/ledger.clj

@@ -25,6 +25,7 @@
    [auto-ap.ssr.ledger.common :as ledger.common]
    [auto-ap.ssr.ledger.investigate :as investigate]
    [auto-ap.ssr.ledger.new :as new]
+   [auto-ap.ssr.ledger.prime-cost :as prime-cost]
    [auto-ap.ssr.ledger.profit-and-loss :as profit-and-loss]
    [auto-ap.ssr.nested-form-params :refer [wrap-nested-form-params]]
    [auto-ap.ssr.svg :as svg]
@@ -737,6 +738,7 @@
           (wrap-client-redirect-unauthenticated))))
    balance-sheet/key->handler
    profit-and-loss/key->handler
+   prime-cost/key->handler
    cash-flows/key->handler
    investigate/key->handler
    new/key->handler)) 

src/clj/auto_ap/ssr/ledger/prime_cost.clj

@@ -0,0 +1,512 @@
+(ns auto-ap.ssr.ledger.prime-cost
+  "Prime Cost Report — what a restaurant sold against what it paid people to sell it.
+
+  Neither figure is interesting alone; the ratio between them is, and it only reads as a trend,
+  which is why this shows eight periods rather than one range.
+
+  The two halves come from deliberately different places. **Payroll is read from the ledger**,
+  because that is where payroll lands once it has been coded to an account — taken from anywhere
+  else it would not tie back to the profit and loss sitting beside it. **Sales are read from the
+  daily sales summaries**, which are the reconciled books rather than the raw till feed.
+
+  That split is why this report sits with the ledger reports despite only half of it being ledger
+  data: it has to agree with the P&L, and it uses `auto-ap.ledger.reports/groupings` for the
+  payroll bands so that agreement is structural rather than a coincidence that survives until
+  somebody edits one of the two lists.
+
+  Reading payroll from the ledger has one consequence worth stating: a journal entry carries the
+  date it was posted, not the span it covers, so a client paying every fortnight puts a fortnight
+  of labour on a single day. Against weekly columns that reads as one enormous week beside one
+  empty one. Hence the period control — set it to the length of the client's pay cycle and the
+  labour line lands where the sales it bought are.
+
+  Replaces the PCR Detail sheet of the `Bi-Weekly` workbook."
+  (:require
+   [auto-ap.datomic :refer [conn]]
+   [auto-ap.graphql.utils :refer [extract-client-ids]]
+   [auto-ap.ledger.reports :as l-reports]
+   [auto-ap.permissions :refer [wrap-must]]
+   [auto-ap.routes.ledger :as route]
+   [auto-ap.routes.utils :refer [wrap-client-redirect-unauthenticated]]
+   [auto-ap.ssr-routes :as ssr-routes]
+   [auto-ap.ssr.components :as com]
+   [auto-ap.ssr.form-cursor :as fc]
+   [auto-ap.ssr.ledger.report-table :refer [table]]
+   [auto-ap.ssr.ui :refer [base-page]]
+   [auto-ap.ssr.utils :refer [apply-middleware-to-all-handlers clj-date-schema
+                              html-response wrap-schema-enforce]]
+   [auto-ap.time :as atime]
+   [bidi.bidi :as bidi]
+   [clj-time.coerce :as coerce]
+   [clj-time.core :as time]
+   [clojure.string :as str]
+   [datomic.api :as dc]
+   [malli.core :as mc]))
+
+(def periods-shown
+  "Eight, as the workbook this replaces used — about the shortest run in which a labour-percentage
+  trend is readable through ordinary noise."
+  8)
+
+(def period-lengths
+  "Selectable column widths, in weeks. Longer columns exist to match a client's pay cycle; see the
+  namespace docstring for why that matters."
+  [{:value "1" :label "Weekly" :weeks 1}
+   {:value "2" :label "Bi-weekly" :weeks 2}
+   {:value "4" :label "Four weeks" :weeks 4}])
+
+(def default-period "1")
+
+(defn weeks-per-period [period]
+  (or (:weeks (first (filter #(= period (:value %)) period-lengths)))
+      1))
+
+(def payroll-bands
+  "`[[label from to] ...]` for payroll, taken from the shared ledger groupings rather than restated
+  here, so this report and the profit and loss can never disagree about what counts as payroll."
+  (:payroll l-reports/groupings))
+
+(def payroll-range
+  "The full span the bands cover, used to filter the query before grouping."
+  {:from (apply min (map second payroll-bands))
+   :to   (inc (apply max (map #(nth % 2) payroll-bands)))})
+
+(defn band-for
+  "The payroll band a numeric account code falls in, or nil when it is not payroll."
+  [code]
+  (some (fn [[label from to]]
+          (when (and code (>= code from) (<= code to)) label))
+        payroll-bands))
+
+(defn period-windows
+  "`[{:starts :ends}]` for the `periods-shown` periods of `weeks` weeks ending at `end-date`, most
+  recent first.
+
+  `:ends` is exclusive, so periods tile and no day is counted twice at a boundary."
+  ([end-date] (period-windows end-date 1))
+  ([end-date weeks]
+   (let [end (coerce/to-date-time end-date)]
+     (for [i (range periods-shown)]
+       {:starts (time/minus end (time/weeks (* weeks (inc i))))
+        :ends   (time/minus end (time/weeks (* weeks i)))}))))
+
+;; ---------------------------------------------------------------------------
+;; Sales — the reconciled daily summaries
+;; ---------------------------------------------------------------------------
+
+(defn revenue-line?
+  "Whether a summary line is revenue rather than tender, tax or tip.
+
+  Revenue is the 40000 block. Tax and tip are liabilities held for someone else, and the tender
+  lines are the money side of the same transaction — none of them are sales."
+  [item]
+  (let [code (get-in item [:ledger-mapped/account :account/numeric-code])]
+    (and code (>= code 40000) (< code 50000))))
+
+(defn signed-amount
+  "A line's contribution to net sales. Credits add and debits subtract, so discounts and returns —
+  posted as debits against revenue accounts — reduce sales with no special casing."
+  [item]
+  (let [amount (or (:ledger-mapped/amount item) 0.0)]
+    (if (= :ledger-side/debit (get-in item [:ledger-mapped/ledger-side :db/ident]))
+      (- amount)
+      amount)))
+
+(defn sales-in-window
+  "`{:total n :by-category {category n}}` of net sales for `client-ids` over `[starts ends)`."
+  [db client-ids starts ends]
+  (let [lines (->> (dc/q '[:find [(pull ?s [{:sales-summary/items
+                                             [:sales-summary-item/category
+                                              :ledger-mapped/amount
+                                              {:ledger-mapped/ledger-side [:db/ident]}
+                                              {:ledger-mapped/account [:account/numeric-code]}]}]) ...]
+                           :in $ [?c ...] ?start ?end
+                           :where
+                           [?s :sales-summary/client ?c]
+                           [?s :sales-summary/date ?d]
+                           [(>= ?d ?start)]
+                           [(< ?d ?end)]]
+                         db client-ids (coerce/to-date starts) (coerce/to-date ends))
+                   (mapcat :sales-summary/items)
+                   (filter revenue-line?))]
+    {:total (reduce + 0.0 (map signed-amount lines))
+     :by-category (reduce (fn [acc item]
+                            (update acc (:sales-summary-item/category item)
+                                    (fnil + 0.0) (signed-amount item)))
+                          {} lines)}))
+
+;; ---------------------------------------------------------------------------
+;; Payroll — the ledger, where coded payroll lands
+;; ---------------------------------------------------------------------------
+
+(defn payroll-in-window
+  "`{:total n :by-band {band-label n} :posted? bool}` of payroll cost for `client-ids` over
+  `[starts ends)`.
+
+  Cost is debits less credits, so a payroll correction posted as a credit reduces the period rather
+  than counting as more labour. `:posted?` records whether any payroll line existed at all, which
+  is not the same question as whether the cost came to zero."
+  [db client-ids starts ends]
+  (let [{:keys [from to]} payroll-range
+        rows (dc/q '[:find ?code ?debit ?credit
+                     :with ?jel
+                     :in $ [?c ...] ?start ?end ?from ?to
+                     :where
+                     [?jel :journal-entry-line/client ?c]
+                     [?jel :journal-entry-line/date ?d]
+                     [(>= ?d ?start)]
+                     [(< ?d ?end)]
+                     [?jel :journal-entry-line/account ?a]
+                     [?a :account/numeric-code ?code]
+                     [(>= ?code ?from)]
+                     [(< ?code ?to)]
+                     [(get-else $ ?jel :journal-entry-line/debit 0.0) ?debit]
+                     [(get-else $ ?jel :journal-entry-line/credit 0.0) ?credit]]
+                   db client-ids (coerce/to-date starts) (coerce/to-date ends) from to)]
+    (reduce (fn [acc [code debit credit]]
+              (let [cost (- (or debit 0.0) (or credit 0.0))]
+                (cond-> (update acc :total + cost)
+                  (band-for code) (update-in [:by-band (band-for code)] (fnil + 0.0) cost))))
+            {:total 0.0 :by-band {} :posted? (boolean (seq rows))}
+            rows)))
+
+;; ---------------------------------------------------------------------------
+;; Assembly
+;; ---------------------------------------------------------------------------
+
+(defn ratio [part whole]
+  (when (and part whole (not (zero? whole)))
+    (/ part whole)))
+
+(defn get-report-data
+  "One column per period, most recent first, each carrying its own sales and payroll."
+  ([db client-ids end-date] (get-report-data db client-ids end-date 1))
+  ([db client-ids end-date weeks]
+   (for [{:keys [starts ends]} (period-windows end-date weeks)]
+     (let [sales (sales-in-window db client-ids starts ends)
+           payroll (payroll-in-window db client-ids starts ends)]
+       {:starts starts
+        :ends ends
+        :sales sales
+        :payroll payroll
+        :labor-ratio (when (:posted? payroll)
+                       (ratio (:total payroll) (:total sales)))}))))
+
+(defn average
+  "Mean of the values that exist, ignoring the ones that do not.
+
+  For a ratio, a missing period is genuinely unknown and has to be left out of the denominator."
+  [xs]
+  (let [xs (remove nil? xs)]
+    (when (seq xs) (/ (reduce + 0.0 xs) (count xs)))))
+
+(defn per-period
+  "Mean over every period, counting one with nothing posted as zero.
+
+  Money is not a ratio: a band that only posts every second period still averages across all of
+  them. Dropping the empty periods from the denominator would let a detail line print larger than
+  the subtotal it is part of."
+  [xs]
+  (when (seq xs)
+    (/ (reduce + 0.0 (map #(or % 0.0) xs)) (count xs))))
+
+(defn category-rows
+  "Sales categories present anywhere in the trend, largest average first.
+
+  Driven by the data rather than a fixed list, so a restaurant that starts selling something new
+  shows it without anyone editing this file."
+  [columns]
+  (->> (into #{} (mapcat (comp keys :by-category :sales)) columns)
+       (map (fn [n] {:label n :values (map #(get-in % [:sales :by-category n]) columns)}))
+       (sort-by #(- (or (per-period (:values %)) 0.0)))))
+
+(defn headline
+  "The three numbers a manager actually opens this report for: the latest labour percentage, what
+  it normally runs at, and which way it moved."
+  [columns]
+  (let [current (first columns)
+        ratios (keep :labor-ratio columns)
+        trend (average (rest ratios))]
+    {:current (:labor-ratio current)
+     :current-sales (get-in current [:sales :total])
+     :current-payroll (get-in current [:payroll :total])
+     :trend trend
+     :delta (when (and (:labor-ratio current) trend)
+              (- (:labor-ratio current) trend))}))
+
+;; ---------------------------------------------------------------------------
+;; Rendering — the shared ledger report table, so this reads like its siblings
+;; ---------------------------------------------------------------------------
+
+(def ^:private hot [185 28 28])   ; labour running above its own trend
+(def ^:private cool [21 128 61])  ; below
+(def ^:private plain [17 24 39])
+
+(defn- heat
+  "Colour for a labour percentage, judged against the trend rather than a fixed target, since the
+  right percentage differs by concept and this report should not pretend to know it."
+  [r trend]
+  (cond
+    (or (nil? r) (nil? trend) (zero? trend)) plain
+    (> r (* trend 1.05)) hot
+    (< r (* trend 0.95)) cool
+    :else plain))
+
+(defn- label-cell
+  "Detail lines sit under their subtotal. The indent is non-breaking spaces because the cell
+  renderer emits the label as text into a `td`, where ordinary leading whitespace collapses away."
+  [label & {:keys [bold indent]}]
+  (cond-> {:value (if indent (str "   " label) label)}
+    bold (assoc :bold true)))
+
+(defn- figure
+  "A numeric cell. The value is always a number, never nil: the shared cell renderer runs
+  `dollars-0?` on it before any nil-punning of its own, so a nil here is an NPE at render time
+  rather than a blank cell."
+  [v fmt & {:keys [bold color]}]
+  (cond-> {:value (or v 0.0) :format fmt}
+    bold (assoc :bold true)
+    color (assoc :color color)))
+
+(def ^:private no-value
+  "An em dash, for a period where the number does not exist — as distinct from being zero."
+  {:value "—" :align :right})
+
+(defn- money-row
+  "Label, average per period, that average's share of sales, then a column per period."
+  [label values sales & {:keys [bold indent]}]
+  (into [(label-cell label :bold bold :indent indent)
+         (figure (per-period values) :dollar :bold bold)
+         (figure (ratio (per-period values) (per-period sales)) :percent)]
+        (for [v values] (figure v :dollar :bold bold))))
+
+(defn- ratio-row
+  "The headline row: payroll as a percentage of the sales it bought.
+
+  A period with no payroll posted gets an em dash rather than 0.0%. Zero labour against real sales
+  is not something a restaurant does; it means the pay run has not landed in the ledger yet, and
+  printing 0.0% would state the opposite."
+  [columns]
+  (let [ratios (map :labor-ratio columns)
+        trend (average ratios)]
+    (into [(label-cell "Payroll as % of sales" :bold true)
+           (figure trend :percent :bold true)
+           {:value ""}]
+          (for [r ratios]
+            (if (nil? r)
+              (assoc no-value :bold true)
+              (figure r :percent :bold true :color (heat r trend)))))))
+
+(defn period-label
+  "`Aug 1` for a one-week column, `Jul 25 – Aug 7` for a longer one — the span, when the span is
+  not obvious from the header alone."
+  [{:keys [starts ends]}]
+  (let [last-day (time/minus ends (time/days 1))
+        short "MMM d"]
+    (if (time/before? starts (time/minus last-day (time/days 6)))
+      (str (atime/unparse-local starts short) " – " (atime/unparse-local last-day short))
+      (atime/unparse-local last-day short))))
+
+(defn report-table
+  "`{:header :rows}` in the shape `auto-ap.ssr.ledger.report-table/table` renders."
+  [columns]
+  (let [sales-totals (map #(get-in % [:sales :total]) columns)
+        payroll-totals (map #(get-in % [:payroll :total]) columns)]
+    {:header [(into [{:value "" :bold true}
+                     {:value "Average" :bold true}
+                     {:value "% of sales" :bold true}]
+                    (for [c columns] {:value (period-label c) :bold true}))]
+     :rows (concat
+            [(money-row "Sales" sales-totals sales-totals :bold true)]
+            (for [{:keys [label values]} (category-rows columns)]
+              (money-row label values sales-totals :indent true))
+            [[] ; a blank row, so sales and payroll read as two blocks rather than one long list
+             (money-row "Payroll" payroll-totals sales-totals :bold true)]
+            (for [[label] payroll-bands
+                  :let [values (map #(get-in % [:payroll :by-band label]) columns)]
+                  :when (some some? values)]
+              (money-row label values sales-totals :indent true))
+            [[]
+             (ratio-row columns)])}))
+
+;; ---------------------------------------------------------------------------
+;; The card
+;; ---------------------------------------------------------------------------
+
+(defn- percent-str [r]
+  (if r (format "%.1f%%" (* 100.0 r)) "—"))
+
+(defn- stat
+  "One figure in the summary strip, big enough to read from across a desk."
+  [{:keys [label value hint color]}]
+  [:div {:class "flex-1 min-w-[9rem] px-5 py-4 rounded-lg bg-gray-50 dark:bg-gray-700"}
+   [:div {:class "text-xs uppercase tracking-wide text-gray-500 dark:text-gray-400"} label]
+   [:div {:class (str "text-2xl font-bold tabular-nums " (or color "text-gray-900 dark:text-white"))}
+    value]
+   (when hint [:div {:class "text-xs text-gray-500 dark:text-gray-400 mt-0.5"} hint])])
+
+(def ^:private spark-w 190)
+(def ^:private spark-h 40)
+
+(defn spark-points
+  "`[[x y] ...]` for the labour percentages, oldest on the left, scaled to fill the box.
+
+  Periods with no payroll posted contribute no point, so the line joins across a gap rather than
+  diving to the floor and inventing a good week."
+  [columns]
+  (let [ratios (reverse (map :labor-ratio columns))
+        present (keep identity ratios)]
+    (when (> (count present) 1)
+      (let [lo (apply min present)
+            span (max 1e-9 (- (apply max present) lo))
+            steps (max 1 (dec (count ratios)))]
+        (keep-indexed
+         (fn [i r]
+           (when r
+             [(+ 3 (* (- spark-w 6) (/ (double i) steps)))
+              (- (- spark-h 3) (* (- spark-h 6) (/ (- r lo) span)))]))
+         ratios)))))
+
+(defn- sparkline
+  "The labour trend as a shape, for the reader who wants the direction before the numbers."
+  [columns]
+  (when-let [pts (spark-points columns)]
+    (let [[lx ly] (last pts)]
+      [:svg {:viewBox (str "0 0 " spark-w " " spark-h)
+             :width spark-w :height spark-h
+             :class "text-gray-400 dark:text-gray-500 mt-1"
+             :role "img"
+             :aria-label "Labour as a percentage of sales, oldest period on the left"}
+       [:polyline {:points (str/join " " (map (fn [[x y]] (str x "," y)) pts))
+                   :fill "none" :stroke "currentColor" :stroke-width "1.5"
+                   :stroke-linejoin "round" :stroke-linecap "round"}]
+       [:circle {:cx lx :cy ly :r "2.5" :class "text-gray-700 dark:text-gray-200"
+                 :fill "currentColor"}]])))
+
+(defn- summary-strip [columns]
+  (let [{:keys [current current-sales current-payroll trend delta]} (headline columns)
+        latest (first columns)]
+    [:div {:class "flex flex-wrap gap-3 mb-5"}
+     (stat {:label "Labour, latest period"
+            :value (percent-str current)
+            :hint (period-label latest)
+            :color (cond
+                     (nil? delta) nil
+                     (pos? delta) "text-red-700 dark:text-red-400"
+                     :else "text-green-700 dark:text-green-400")})
+     (stat {:label "Usual"
+            :value (percent-str trend)
+            :hint (str "prior " (dec periods-shown) " periods")})
+     (stat {:label "Change"
+            :value (if delta
+                     (format "%+.1f pts" (* 100.0 delta))
+                     "—")
+            :hint (if delta "against the usual" "no payroll posted yet")
+            :color (cond
+                     (nil? delta) nil
+                     (pos? delta) "text-red-700 dark:text-red-400"
+                     :else "text-green-700 dark:text-green-400")})
+     (stat {:label "Sales, latest period"
+            :value (format "$%,.0f" (or current-sales 0.0))
+            :hint (format "on $%,.0f of payroll" (or current-payroll 0.0))})
+     (when-let [line (sparkline columns)]
+       [:div {:class "flex-1 min-w-[11rem] px-5 py-4 rounded-lg bg-gray-50 dark:bg-gray-700"}
+        [:div {:class "text-xs uppercase tracking-wide text-gray-500 dark:text-gray-400"}
+         "Labour trend"]
+        line
+        [:div {:class "text-xs text-gray-500 dark:text-gray-400 mt-0.5"} "oldest to latest"]])]))
+
+(defn- footnote []
+  [:p {:class "text-xs text-gray-500 dark:text-gray-400 mt-4 max-w-3xl"}
+   "Sales are net revenue from the daily sales summaries — discounts and returns subtract, and tax, "
+   "tips and tender are excluded. Payroll is the ledger's payroll accounts, debits less credits, on "
+   "the date each entry was posted. A period showing "
+   [:span {:class "font-medium"} "—"]
+   " had no payroll posted at all; if that alternates, set the period to the client's pay cycle."])
+
+(defn prime-cost-card* [{:keys [request columns]}]
+  (let [params (:query-params request)]
+    (com/content-card
+     {:class "w-full" :id "prime-cost-report"}
+     [:div {:class "flex flex-col px-8 py-8"}
+      [:h1.text-2xl.font-bold "Prime Cost Report"]
+      [:p {:class "text-sm text-gray-600 dark:text-gray-400 mt-1 mb-5"}
+       "Sales against the payroll that earned them, over "
+       (str periods-shown)
+       " periods. Payroll from the ledger, sales from the daily summaries."]
+
+      [:form {:hx-get (bidi/path-for ssr-routes/only-routes ::route/run-prime-cost)
+              :hx-target "#prime-cost-report"
+              :hx-swap "outerHTML"
+              :class "mb-6"}
+       (fc/start-form
+        params
+        (:form-errors request)
+        [:div {:class "flex flex-wrap gap-3 items-end"}
+         (fc/with-field :end-date
+           (com/validated-field {:label "Period ending" :errors (fc/field-errors)}
+                                [:div {:class "w-48"}
+                                 (com/date-input {:name (fc/field-name)
+                                                  :class "w-48"
+                                                  :value (some-> (fc/field-value)
+                                                                 coerce/to-date-time
+                                                                 (atime/unparse-local atime/normal-date))})]))
+         (fc/with-field :period
+           (com/validated-field {:label "Period length" :errors (fc/field-errors)}
+                                [:div {:class "w-40"}
+                                 (com/select {:name (fc/field-name)
+                                              :class "w-40"
+                                              :value (or (fc/field-value) default-period)
+                                              :options (map (juxt :value :label) period-lengths)})]))
+         [:div {:class "pb-1"}
+          (com/button {:color :primary :class "w-24"} "Run")]])]
+
+      (if (seq columns)
+        [:div
+         (summary-strip columns)
+         (table {:table (report-table columns)
+                 :widths (into [16 9 7] (repeat periods-shown 9))
+                 :height "max-h-[70vh]"})
+         (footnote)]
+        [:div {:class "text-gray-600 dark:text-gray-400 py-6"}
+         "Choose a period-ending date and run the report."])])))
+
+(defn page [request]
+  (base-page
+   request
+   (com/page {:nav com/company-aside-nav
+              :client-selection (:client-selection request)
+              :client (:client request)
+              :clients (:clients request)
+              :identity (:identity request)}
+             (com/breadcrumbs {}
+                              [:a {:href (bidi/path-for ssr-routes/only-routes ::route/prime-cost)}
+                               "Prime Cost Report"])
+             (prime-cost-card* {:request request :columns nil}))
+   "Prime Cost Report"))
+
+(defn run [{{:keys [end-date period]} :query-params :as request}]
+  (let [client-ids (extract-client-ids (:clients request)
+                                       (:client-id request)
+                                       (when (:client-code request)
+                                         [:client/code (:client-code request)]))
+        columns (when end-date
+                  (get-report-data (dc/db conn) client-ids end-date
+                                   (weeks-per-period (or period default-period))))]
+    (html-response (prime-cost-card* {:request request :columns columns}))))
+
+(def query-schema
+  (mc/schema
+   [:maybe [:map
+            [:end-date {:optional true} [:maybe clj-date-schema]]
+            [:period {:optional true} [:maybe (into [:enum] (map :value period-lengths))]]]]))
+
+(def key->handler
+  (apply-middleware-to-all-handlers
+   {::route/prime-cost page
+    ::route/run-prime-cost run}
+   (fn [h]
+     (-> h
+         (wrap-schema-enforce :query-schema query-schema)
+         (wrap-must {:activity :read :subject :profit-and-loss})
+         (wrap-client-redirect-unauthenticated)))))

src/clj/auto_ap/ssr/ledger/report_table.clj

@@ -7,21 +7,20 @@
    [hiccup.util :as hu]
    [iol-ion.query :as query]))
 
-
-
 (defn cell [{:keys [width investigate-url other-style]} c]
   (let [cell-contents (cond
 
                         (= :dollar (:format c))
-                        (format "$%,.2f" (if (query/dollars-0? (:value c))
+                        (format "$%,.2f" (if (or (nil? (:value c))
+                                                 (query/dollars-0? (:value c)))
                                            0.0
                                            (:value c)))
 
-                      
                         (= :percent (:format c))
-                        (format "%%%.1f" (if (query/dollars-0? (:value c))
+                        (format "%.1f%%" (if (or (nil? (:value c))
+                                                 (query/dollars-0? (:value c)))
                                            0.0
-                                           (* 100.0 (or (:value c) 0.0))))
+                                           (* 100.0 (:value c))))
 
                         :else
                         (str (:value c)))
@@ -32,8 +31,7 @@
                                                      (inst? (:date-range (:filters c))) (assoc :end-date (atime/unparse-local (coerce/to-date-time (:date-range (:filters c))) atime/normal-date))
                                                      (:end (:date-range (:filters c))) (assoc :end-date (atime/unparse-local (coerce/to-date-time (:end (:date-range (:filters c)))) atime/normal-date))
                                                      (:start (:date-range (:filters c))) (assoc :start-date (atime/unparse-local (coerce/to-date-time (:start (:date-range (:filters c)))) atime/normal-date))
-                                                     (:client-id (:filters c))  (assoc :client-id (:client-id (:filters c))))
+                                                     (:client-id (:filters c))  (assoc :client-id (:client-id (:filters c)))))}
-                                                   )}
                                   cell-contents)
                         cell-contents)]
     [:td.px-4.py-2
@@ -45,8 +43,7 @@
                                           (->> (:border c)
                                                (map
                                                 (fn [b]
-                                                   [(keyword (str "border-" (name b))) "1px solid black"])
+                                                  [(keyword (str "border-" (name b))) "1px solid black"]))
-                                                 )
                                                (into s))))
        (:colspan c)             (assoc :colspan (:colspan c))
        (:align c)               (assoc :align (:align c))
@@ -70,10 +67,13 @@
       (apply max counts)
       0)))
 
-(defn table [{:keys [table widths investigate-url warning]}]
+(defn table [{:keys [table widths investigate-url warning height]}]
   (let [cell-count (cell-count table)]
     (com/content-card {:class "inline-block overflow-scroll"}
-                        [:div {:class "overflow-scroll h-[70vh] m-4 inline-block"}
+                      ;; `height` is a Tailwind height class, defaulting to the fixed 70vh the long
+                      ;; reports need. A short report can pass `max-h-[70vh]` and then takes only
+                      ;; the room it uses, rather than leaving a blank pane below itself.
+                      [:div {:class (str "overflow-scroll m-4 inline-block " (or height "h-[70vh]"))}
                        (when warning [:div.rounded.bg-red-50.text-red-800.p-4.m-2
                                       warning])
                        (-> [:table {:class "text-sm text-left text-gray-500 dark:text-gray-400"}

src/cljc/auto_ap/routes/ledger.cljc

@@ -24,4 +24,6 @@
                                        "/export" ::export-cash-flows}
              "/reports/profit-and-loss" {"" ::profit-and-loss
                                        "/run" ::run-profit-and-loss
-                                       "/export" ::export-profit-and-loss}})
+                                       "/export" ::export-profit-and-loss}
+             "/reports/prime-cost" {"" ::prime-cost
+                                    "/run" ::run-prime-cost}})

test/clj/auto_ap/ssr/ledger/prime_cost_test.clj

@@ -0,0 +1,218 @@
+(ns auto-ap.ssr.ledger.prime-cost-test
+  (:require
+   [auto-ap.datomic :refer [conn]]
+   [auto-ap.integration.util :refer [setup-test-data wrap-setup]]
+   [auto-ap.ledger.reports :as l-reports]
+   [auto-ap.ssr.ledger.prime-cost :as sut]
+   [clj-time.coerce :as coerce]
+   [clj-time.core :as time]
+   [clojure.test :refer [deftest is testing use-fixtures]]
+   [datomic.api :as dc]))
+
+(use-fixtures :each wrap-setup)
+
+(def week-ending (time/date-time 2026 8 10))
+(def in-week #inst "2026-08-05T12:00:00.000-00:00")
+(def week-before #inst "2026-07-29T12:00:00.000-00:00")
+
+(defn- account [tempid code]
+  {:db/id tempid :account/name (str "Account " code) :account/numeric-code code})
+
+(defn- jel [client account-tempid date debit]
+  {:journal-entry-line/client client
+   :journal-entry-line/account account-tempid
+   :journal-entry-line/date date
+   :journal-entry-line/debit debit})
+
+(deftest period-windows-tile-without-gaps
+  (testing "each period ends where the next begins, so no day is counted twice or missed"
+    (let [ws (sut/period-windows week-ending)]
+      (is (= sut/periods-shown (count ws)))
+      (is (= (coerce/to-date week-ending) (coerce/to-date (:ends (first ws))))
+          "the newest window ends at the requested date")
+      (is (every? (fn [[newer older]] (= (:starts newer) (:ends older)))
+                  (partition 2 1 ws))
+          "windows abut")
+      (is (apply > (map (comp coerce/to-long :starts) ws))
+          "most recent first")))
+  (testing "a longer period widens each column without leaving a gap between them"
+    (let [ws (sut/period-windows week-ending 2)]
+      (is (= sut/periods-shown (count ws)))
+      (is (= 14 (time/in-days (time/interval (:starts (first ws)) (:ends (first ws))))))
+      (is (every? (fn [[newer older]] (= (:starts newer) (:ends older)))
+                  (partition 2 1 ws))))))
+
+(deftest period-length-select-maps-to-weeks
+  (testing "the query param the form submits resolves to a column width"
+    (is (= 1 (sut/weeks-per-period "1")))
+    (is (= 2 (sut/weeks-per-period "2")))
+    (is (= 1 (sut/weeks-per-period nil)) "an absent or unknown period falls back to weekly")))
+
+(deftest payroll-bands-come-from-the-shared-ledger-groupings
+  (testing "the bands are the ledger's, not a second list that can drift from the P&L"
+    (is (= (:payroll l-reports/groupings) sut/payroll-bands)))
+  (testing "every payroll account code lands in exactly one band"
+    (is (some? (sut/band-for 60500)) "general payroll is not orphaned")
+    (is (some? (sut/band-for 61100)))
+    (is (some? (sut/band-for 62200)))
+    (is (some? (sut/band-for 63200)))
+    (is (some? (sut/band-for 65000)))
+    (is (some? (sut/band-for 69800)))
+    (is (nil? (sut/band-for 50000)) "food cost is not payroll")
+    (is (nil? (sut/band-for 70000)) "controllable costs are not payroll")))
+
+(deftest payroll-is-debits-less-credits-within-the-week
+  (testing "a credit correction reduces the week rather than counting as more labour, and lines
+            outside the window are excluded"
+    (let [{:strs [test-client-id]} (setup-test-data [])]
+      @(dc/transact conn [(account "foh" 63200)
+                          (account "boh" 62200)
+                          (jel test-client-id "foh" in-week 1000.0)
+                          (jel test-client-id "boh" in-week 400.0)
+                          {:journal-entry-line/client test-client-id
+                           :journal-entry-line/account "foh"
+                           :journal-entry-line/date in-week
+                           :journal-entry-line/credit 100.0}
+                          (jel test-client-id "foh" week-before 999.0)])
+      (let [{:keys [total by-band]} (sut/payroll-in-window
+                                     (dc/db conn) [test-client-id]
+                                     (time/minus week-ending (time/weeks 1)) week-ending)]
+        (is (= 1300.0 total) "1000 + 400 - 100, and nothing from the prior week")
+        (is (= 900.0 (get by-band "63000-66000 Payroll - FOH")))
+        (is (= 400.0 (get by-band "62000 Payroll - BOH")))))))
+
+(deftest payroll-excludes-non-payroll-accounts
+  (testing "only the 60000 block counts, so food cost never lands in labour"
+    (let [{:strs [test-client-id]} (setup-test-data [])]
+      @(dc/transact conn [(account "foh" 63200)
+                          (account "food" 50000)
+                          (jel test-client-id "foh" in-week 500.0)
+                          (jel test-client-id "food" in-week 5000.0)])
+      (is (= 500.0 (:total (sut/payroll-in-window
+                            (dc/db conn) [test-client-id]
+                            (time/minus week-ending (time/weeks 1)) week-ending)))))))
+
+(deftest sales-count-revenue-only-and-net-of-discounts
+  (testing "tender, tax and tip are not sales, and a debit against revenue reduces it"
+    (let [{:strs [test-client-id]} (setup-test-data [])]
+      @(dc/transact conn [(account "food-rev" 40111)
+                          (account "discount" 41000)
+                          (account "tax" 25700)
+                          (account "card" 75460)
+                          {:sales-summary/client test-client-id
+                           :sales-summary/date in-week
+                           :sales-summary/client+date [test-client-id in-week]
+                           :sales-summary/items
+                           [{:sales-summary-item/category "Gyros"
+                             :ledger-mapped/amount 1000.0
+                             :ledger-mapped/ledger-side :ledger-side/credit
+                             :ledger-mapped/account "food-rev"}
+                            {:sales-summary-item/category "Discounts"
+                             :ledger-mapped/amount 100.0
+                             :ledger-mapped/ledger-side :ledger-side/debit
+                             :ledger-mapped/account "discount"}
+                            {:sales-summary-item/category "Tax"
+                             :ledger-mapped/amount 90.0
+                             :ledger-mapped/ledger-side :ledger-side/credit
+                             :ledger-mapped/account "tax"}
+                            {:sales-summary-item/category "Card Payments"
+                             :ledger-mapped/amount 990.0
+                             :ledger-mapped/ledger-side :ledger-side/debit
+                             :ledger-mapped/account "card"}]}])
+      (let [{:keys [total by-category]} (sut/sales-in-window
+                                         (dc/db conn) [test-client-id]
+                                         (time/minus week-ending (time/weeks 1)) week-ending)]
+        (is (= 900.0 total) "1000 of revenue less a 100 discount; tax and tender excluded")
+        (is (= 1000.0 (get by-category "Gyros")))
+        (is (= -100.0 (get by-category "Discounts")))
+        (is (nil? (get by-category "Tax")) "tax is money held for someone else, not a sale")
+        (is (nil? (get by-category "Card Payments")) "tender is the other side of the sale")))))
+
+(deftest the-headline-ratio-is-payroll-over-sales
+  (testing "the number the report exists for"
+    (let [{:strs [test-client-id]} (setup-test-data [])]
+      @(dc/transact conn [(account "food-rev" 40111)
+                          (account "foh" 63200)
+                          (jel test-client-id "foh" in-week 250.0)
+                          {:sales-summary/client test-client-id
+                           :sales-summary/date in-week
+                           :sales-summary/client+date [test-client-id in-week]
+                           :sales-summary/items
+                           [{:sales-summary-item/category "Gyros"
+                             :ledger-mapped/amount 1000.0
+                             :ledger-mapped/ledger-side :ledger-side/credit
+                             :ledger-mapped/account "food-rev"}]}])
+      (let [columns (sut/get-report-data (dc/db conn) [test-client-id] week-ending)
+            current (first columns)]
+        (is (= sut/periods-shown (count columns)))
+        (is (= 0.25 (:labor-ratio current)) "250 of labour against 1000 of sales")
+        (is (nil? (:labor-ratio (second columns)))
+            "a week with no sales has no ratio rather than a divide-by-zero")))))
+
+(deftest a-period-with-no-payroll-posted-has-no-ratio
+  (testing "payroll posted on a pay-period date leaves neighbouring weeks empty, and an empty week
+            must read as unknown rather than as 0% labour"
+    (let [{:strs [test-client-id]} (setup-test-data [])]
+      @(dc/transact conn [(account "food-rev" 40111)
+                          {:sales-summary/client test-client-id
+                           :sales-summary/date in-week
+                           :sales-summary/client+date [test-client-id in-week]
+                           :sales-summary/items
+                           [{:sales-summary-item/category "Gyros"
+                             :ledger-mapped/amount 1000.0
+                             :ledger-mapped/ledger-side :ledger-side/credit
+                             :ledger-mapped/account "food-rev"}]}])
+      (let [current (first (sut/get-report-data (dc/db conn) [test-client-id] week-ending))]
+        (is (= 1000.0 (get-in current [:sales :total])) "the sales are real")
+        (is (false? (get-in current [:payroll :posted?])))
+        (is (nil? (:labor-ratio current))
+            "no payroll line exists, so the ratio is unknown, not zero")))))
+
+(deftest report-table-renders-a-column-per-week-plus-label-and-average
+  (testing "the table lines up with its header"
+    (let [{:strs [test-client-id]} (setup-test-data [])]
+      @(dc/transact conn [(account "food-rev" 40111)
+                          {:sales-summary/client test-client-id
+                           :sales-summary/date in-week
+                           :sales-summary/client+date [test-client-id in-week]
+                           :sales-summary/items
+                           [{:sales-summary-item/category "Gyros"
+                             :ledger-mapped/amount 1000.0
+                             :ledger-mapped/ledger-side :ledger-side/credit
+                             :ledger-mapped/account "food-rev"}]}])
+      (let [{:keys [header rows]} (sut/report-table
+                                   (sut/get-report-data (dc/db conn) [test-client-id] week-ending))
+            width (+ 3 sut/periods-shown)]
+        (is (= width (count (first header))))
+        (is (every? #(= width (count %)) (remove empty? rows))
+            "every populated row is the same width as the header, or the table skews")))))
+
+(deftest the-trend-line-skips-periods-with-no-payroll
+  (testing "a period with no payroll posted contributes no point, so the line joins across the gap
+            rather than diving to the floor and drawing a week that never happened"
+    (let [columns [{:labor-ratio 0.30} {:labor-ratio nil} {:labor-ratio 0.20}]]
+      (is (= 2 (count (sut/spark-points columns))))))
+  (testing "a single readable period is not a trend"
+    (is (nil? (sut/spark-points [{:labor-ratio 0.30} {:labor-ratio nil}])))))
+
+(deftest a-detail-line-never-averages-larger-than-its-subtotal
+  (testing "money averages over every period, so a band posting every second period is not divided
+            by a smaller denominator than the total it rolls up into"
+    (is (= 500.0 (sut/per-period [1000.0 nil 1000.0 nil]))
+        "the empty periods still count")
+    (is (= 1000.0 (sut/average [1000.0 nil 1000.0 nil]))
+        "a ratio, by contrast, only averages the periods it is known for"))
+  (testing "on real-shaped data the payroll bands sum to no more than the payroll total"
+    (let [{:strs [test-client-id]} (setup-test-data [])]
+      @(dc/transact conn [(account "foh" 63200)
+                          (jel test-client-id "foh" in-week 1400.0)])
+      (let [{:keys [rows]} (sut/report-table
+                            (sut/get-report-data (dc/db conn) [test-client-id] week-ending))
+            average-of (fn [label]
+                         (->> rows
+                              (filter #(= label (-> (str (:value (first %)))
+                                                    (clojure.string/replace "\u00a0" "")
+                                                    (clojure.string/trim))))
+                              first second :value))]
+        (is (= (average-of "Payroll") (average-of "63000-66000 Payroll - FOH"))
+            "one band carrying all the payroll averages exactly what the total does")))))