At a glance
- Robust z-score against the same weekday over the previous 8 weeks
- Sustained decline = last 14 days < 75% of the 8 weeks before. If it also fell last year, it's labelled seasonal
- Shrinkage = physical count below SAP beyond tolerance; a count gain suggests a receiving or GR error
How it works
- For each product and day, Shelly compares the day with the median of the same weekday in the last 8 weeks.
- It uses the median and MAD (median absolute deviation) instead of mean and standard deviation, so one odd day can't distort the baseline.
- Flags worth less than $40 are dropped to reduce noise. The thresholds tune themselves from your decisions.
How to read it
- A drop plus plenty of stock on hand points to a shelf or display problem, not a stock-out.
- A shrinkage flag marked 'repeat' is worth a CCTV review; 'first time' may be a counting error.
Limits & safeguards
- Daily data can't show time-of-day problems. Hourly POS data is on the roadmap.
Ask Shelly
Any problems this week?Any shrinkage?How's waste?
Type or say these in the chat on the main page.