Spotting
margin drift.

Margin drift is the silent killer of small-shop profitability. Costs creep up by a few percent, you don't pass them through, the margin shrinks invisibly over months. The drift insight surfaces this before it becomes a real problem.

01 What is margin drift?

A product's margin contribution is its sale price minus VAT minus COGS, multiplied by units sold. Margin drift is when that contribution shrinks week-over-week without an obvious cause — sales hold steady, but the margin per unit quietly slips. It's easy to miss day-by-day because each week's change is small; over a four-week trend the slow leak becomes obvious.

02 How does nouz flag margin drift?

In the Insights panel on Statistics, a margin drift tag fires when a product's per-unit margin drops by more than ~10% over a four-week rolling window. The card shows which product, which direction, and the per-unit change. You can click in for the chart.

03 What should I check first when drift fires?

There are three likely causes, in order. Most often COGS crept up — your supplier raised wholesale prices but the product's COGS field still shows the old number, so update it. Or your sale price stayed flat while costs rose, and you didn't pass them through. Or the mix shifted toward a cheaper variant, which reads similar but isn't technically drift. Details below.

• COGS crept up — your supplier raised wholesale prices, but your product's COGS field still says the old number. Update it.
• Sale price stayed flat — costs went up, you didn't pass them through. Decide whether to.
• Mix shifted — you're selling more of the cheaper variant. Not technically drift, but reads similar.

04 How do I fix margin drift once I find it?

Once you've identified the cause, the fixes are short. If COGS crept up, open the product, bump the COGS field, and save — future sales use the new value and the insight dims within a week. If your sale price needs to follow, raise it enough to restore margin. If the mix shifted, decide whether to push the higher-margin variant or accept the reality. Steps follow.

• If COGS crept up: open the product, bump the COGS field, save. Future sales use the new value. The drift insight will dim within a week.
• If sale price needs to follow: raise the price by enough to restore margin. Most owners under-raise prices; the drift insight is a license to fix that.
• If mix shifted: consider whether you want to push the higher-margin variant more, or accept the lower-margin reality.