What is velocity?
How quickly products sell. Data Purl does not observe unit sales; it provides shelf signals that indicate velocity, such as full-price sell-out and time to markdown.
Definition
Velocity usually means units sold per period. Data Purl measures what is visible on retailer websites (prices, markdowns, availability and assortment), not transactions, so it does not report unit sales velocity.
What the shelf does show are signals that move with velocity: how fast sizes sell out at full price, how long products hold full price before being marked down, and how quickly restocked sizes sell out again.
How Data Purl measures it
Velocity signals are built from weekly SKU-level availability and price histories: time from first seen to first markdown, share of sizes selling out at full price, and restock patterns.
Why it matters
For investors these signals lead reported sales: strong full-price sell-out and late markdowns tend to precede good sell-through and margins.
Pitfalls
- Treat these as indicators of velocity, not measured unit sales. Pair them with transaction data where exact volumes are needed.
See the data for your coverage
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