Start with a defined question, such as whether a particular size moved more often during the last comparable month. Pull the dates and quantities from recorded counter transactions, then check whether the item was actually available throughout that period.
A tally is history, not a forecast. A stockout, a promotion, a closed day, or an unusual bulk purchase can make a product appear more or less popular than normal. Mark those events beside the figures and compare like periods only when operating days and availability are reasonably similar.
Use the pattern to plan a small, reversible check rather than placing a large order. Record what changed, the quantity purchased, and what happened afterward; a later result still does not prove that the same demand will continue. POS records can support better questions, but they do not establish future customer demand.
