Why growth slowed in week 27.
A retail chain’s sales growth halved in a single week, from +17.4% to +7.3%, and its plan beat narrowed to the thinnest margin in seven weeks. This is what the data said, how long it took to find, and what it is worth to fix. All figures measured against the live database; the client is anonymised throughout.
- More customers came in, and fewer of them bought. Footfall rose 4.0% in week 27 and 26.6% across the six weeks, while conversion fell from 18.5% to 17.5%. Demand was not the problem.
- Most of the slowdown was not a slowdown. Last year's week 27 was 6.7% bigger than its week 26, so the comparison hardened on its own.
- The real decline was availability — and it cost transactions, not basket size. Basket composition was tested against availability at department and store level and shows no relationship. Fewer customers found what they came for, worth about $101,000 in week 27 alone across the sixteen measured stores.
- The cause sits upstream. The business has bought 0.74 units for every unit sold this year. Warehouses absorbed the gap until they could not.
1. The week in question
The headline drop is 10.1 points. Splitting it matters, because nearly three quarters of it is arithmetic rather than performance:
| Component | Points | What it is |
|---|---|---|
| Harder prior-year base | 7.3 | Would have happened with sales flat week on week |
| Actual sales decline | 2.8 | The part that is genuinely this year |
2. More customers came in. Fewer of them bought.
Sixteen stores report door count across the whole six-week window. Their traffic, transactions and conversion, week by week:
| Retail week | Traffic | Transactions | Conversion | Sales |
|---|---|---|---|---|
| 22 | 169,801 | 30,359 | 17.88% | 1,365,896 |
| 23 | 171,327 | 31,626 | 18.46% | 1,470,925 |
| 24 | 182,021 | 33,988 | 18.67% | 1,590,175 |
| 25 | 199,717 | 36,995 | 18.52% | 1,726,489 |
| 26 | 206,753 | 38,185 | 18.47% | 1,793,796 |
| 27 | 214,994 | 37,539 | 17.46% | 1,744,690 |
That is not a demand problem. The customers arrived; the sale did not happen.
2.1 What the conversion drop cost, in one week
Had week 27 converted at week 26's rate, its 214,994 visitors would have produced 39,707 transactions rather than 37,539. At the week's own average ticket of $46.48 that is roughly $101,000 of sales, in one week, across sixteen stores — before counting the nine sites without door counters.
2.2 And the baskets themselves held
If shoppers were being turned away by empty shelves, the baskets that did get rung should show it — thinner, fewer add-ons, more single-item sales. Across 214,818 transactions in the window, they barely moved.
| Basket measure | Weeks 22–26 | Week 27 | Change |
|---|---|---|---|
| Baskets analysed | 176,129 | 38,689 | — |
| Single-style baskets | 40.0% | 40.7% | +0.7 pts |
| Two styles or more | 60.0% | 59.3% | −0.7 pts |
| Three styles or more | 35.3% | 34.2% | −1.1 pts |
| Styles per basket | 2.46 | 2.42 | −0.04 |
| Units per basket | 2.78 | 2.62 | −0.16 |
There is a compositional shift underneath — the share of baskets containing each department moved more than the totals suggest:
| Department | In weeks 22–26 | In week 27 | Change | In-stock change |
|---|---|---|---|---|
| Department 1 | 65.9% | 65.3% | −0.6 pts | −4.0 pts |
| Department 5 | 47.9% | 45.3% | −2.6 pts | −1.7 pts |
| Department 4 | 37.4% | 41.7% | +4.3 pts | −2.8 pts |
The same test at store level returns the same answer. Across the ten largest stores, in-stock fell between 3.0 and 6.7 points, while units per basket moved between +0.26 and −0.16 — noise, with no relationship to the availability change. One store lost 6.7 points of in-stock and its basket was flat; another lost 4.9 points and its basket grew.
3. The root cause: the buy has not kept pace with the sell
For every four units sold this year, three have been bought. The difference came out of inventory. The warehouses absorbed it for most of the year — which is precisely why nothing appeared in the sales line until the buffer thinned.
| Retail week | Warehouse stock | Store stock | Store cover | In-stock |
|---|---|---|---|---|
| 22 | 992,580 | 579,741 | 0.99 | 83.1% |
| 23 | 985,279 | 586,640 | 1.13 | 82.6% |
| 24 | 931,134 | 582,578 | 0.90 | 81.8% |
| 25 | 890,108 | 575,720 | 1.00 | 80.6% |
| 26 | 839,485 | 563,341 | 0.86 | 79.1% |
| 27 | 804,313 | 537,872 | 0.73 | 77.6% |
Store cover is units flowing into stores divided by units sold. Above 1.0 the network builds stock; below it, drains. The warehouses drained nearly three times faster than the stores — −19% against −7% — which is the signature of a distribution network working correctly against an inbound supply that is too small. The goods were not stuck in the warehouse. They were never bought.
4. Where it bites: the A stores
The seven highest-selling stores carry the trade, and every one of them was short-fed over the six weeks to 8 August.
| Store | Units sold | Stock, start | Stock, end | Change | Weeks cover | Received per unit sold | In-stock |
|---|---|---|---|---|---|---|---|
| Store A1 | 75,206 | 77,272 | 66,919 | −13.4% | 5.3 | 0.87 | 80.5% |
| Store A2 | 61,659 | 32,655 | 25,304 | −22.5% | 2.5 | 0.89 | 83.4% |
| Store A3 | 61,412 | 69,210 | 57,206 | −17.3% | 5.6 | 0.83 | 84.6% |
| Store A4 | 44,515 | 17,758 | 17,256 | −2.8% | 2.3 | 0.98 | 86.9% |
| Store A5 | 41,242 | 29,247 | 23,946 | −18.1% | 3.5 | 0.87 | 87.8% |
| Store A6 | 39,829 | 38,186 | 34,082 | −10.7% | 5.1 | 0.92 | 85.7% |
| Store A7 | 35,323 | 41,503 | 31,773 | −23.4% | 5.4 | 0.74 | 83.4% |
Meanwhile a mid-volume store sits on 11.6 weeks' cover and 37 units per square foot, roughly double the chain norm. The surplus is not where the trade is.
4.1 And the stock the A stores hold is the wrong stock
At the busiest stores, 19–22% of units sit in styles with a broken size run, and only about a third of styles are complete on both size and colour. Four in five of the missing sizes do not exist anywhere in the network — which is the replacement ratio showing up on the shop floor. Runs break as they sell through, and there is nothing behind them to repair with.
5. What we had to build to answer the question
We rebuilt it. Anchoring on the current snapshot and walking the movement ledger backwards produced a daily stock position for every SKU at every site: 3.8 million rows across 43 days, with the anchor day reconciling exactly to the live snapshot and zero day-over-day discontinuities. Every in-stock and cover figure in this document comes from it.
6. What it is worth
From the companion distribution analysis, measured on the same database:
| Action | Units | Retail value | Comment |
|---|---|---|---|
| Ship what the warehouses already hold | 93,177 | $1,686,206 | Bought, paid for, sitting still |
| Rebalance surplus between stores | 8,718 | $138,336 | Matched shortage against genuine surplus |
| Consolidate dead broken runs out of A stores | 16,571 | — | 720 styles; frees prime selling space |
A 21-point improvement in service level using stock the business already owns. No purchase order, no additional working capital.
7. Proposed engagement
Four workstreams. Each stands alone and delivers on its own; none waits on the one after it.
| # | Workstream | What it delivers | Why now |
|---|---|---|---|
| 1 | Full insights analysis | The complete diagnostic across trading, availability, assortment and supply — with the stock-history layer made permanent so the questions stay answerable. | Today the history has to be reconstructed each time. A nightly snapshot makes every future question a query rather than a project. |
| 2 | Immediate DC distribution and re-allocation | Ship the $1.69M the warehouses already hold; rebalance $138k between stores; pull 16,571 units of dead broken runs out of A-store space. | Fastest return in the programme and it needs no forecast. Same pick lists, same warehouse process — only the quantities and the order change. |
| 3 | Forecast-based purchasing | Replace the static minimum with a demand-derived target as the buying driver, keeping pack rounding and presentation floors intact. | The 0.74 replacement ratio is the root cause. Distribution moves what exists; only buying changes how much exists. |
| 4 | Weekly assortment planning | Size and colour completeness by store and grade, reviewed weekly, with the replenish-versus-clear decision made on velocity rather than on age. | Runs break continuously at the A stores. A weekly cadence catches them while they are still repairable. |
8. Basis, and what this analysis does not claim
- Full dataset, no sampling. Every figure is measured against a full copy of the live trading data. Trading, availability and movement figures cover retail weeks 22–27, complete to the end of week 27.
- Availability is measured, causation is inferred. The chain of evidence — receipts below sales, warehouses draining, in-stock falling, traffic rising while conversion falls — is consistent and each link is measured. It is not a controlled experiment, and the per-store correlation between availability and sales is not strong enough to attribute a precise revenue figure to any single store.
- Traffic is measured within the six-week window only, on a fixed panel of the sixteen stores reporting door count throughout. Year-on-year traffic comparison is excluded because counter coverage changed during the year. The $101,000 figure covers those sixteen stores for one week and is not annualised.
- Unmet demand is not lost revenue. Customers substitute, defer and return. The recoverable figures above are gross exposure; a measured substitution rate is a workstream 1 deliverable rather than an assumption baked in here.
- Full size and colour runs improve availability, not obviously sell-through. Across all seventeen stores, complete styles are in stock materially more often but do not demonstrably sell through faster. The presentation rule is recommended on the availability evidence, and the sell-through question is left for a controlled pilot.
Measured against a full copy of the live trading data — complete dataset, no sampling. Trading, traffic and availability figures cover retail weeks 22–27 and derive from a reconstructed daily stock history built for this analysis. Traffic is a fixed panel of the sixteen stores reporting door count across the whole window. Store names and locations are anonymised; all figures are unchanged.
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