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  • Platform
    • Coverage400+ retailers, history back to 2013
    • Shelf IndicesFree monthly price and discount indices
    • Brand headlinesQuarterly prices for 84 consumer brands
    • Custom dataExtracts scoped to your sectors and dates
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      MethodologyHow we collect, classify and map brands
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  1. Home
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  3. /Tracking holiday and event promotions year on year
Use case

How do you measure whether retailers are more promotional this holiday season than last year?

Holiday promotions are only comparable when the same events are lined up year on year: Black Friday, Cyber Monday, Prime Day and end-of-season sales move between calendar weeks. Align the events, then compare markdown breadth, discount depth and full-price availability for the same retailers and categories. A season that needs deeper, broader discounts to clear stock points to margin pressure.

For:Public market investorsConsultantsPrivate equity

Last reviewed 24 September 2026

Align the calendar first

Thanksgiving falls on a different date each year, so Black Friday and Cyber Monday shift by up to a week, and marketplace events such as Prime Day move between months. Comparing calendar weeks directly will show false increases and decreases. Align on the event, not the date.

What to compare

  • Markdown breadth: how much of the range is discounted during the event window.
  • Discount depth: how large the discounts are on promoted products.
  • Promotion start date: retailers starting earlier than last year is itself a signal.
  • Full-price availability after the event: what did not sell through at full price.

A practical workflow

  1. 1Choose the retailers and categories that matter for the company or theme.
  2. 2Line up event windows for this year and the prior two years.
  3. 3Compare breadth, depth and duration inside each window.
  4. 4Check the weeks after the event for continued clearance.

Metrics used

  • Promotional intensity: How heavily a brand, retailer or category relies on discounts, combining how often products are promoted and how deep the discounts are.
  • Markdown breadth: The share of each product's in-stock sizes and variants selling below full price, averaged across products so each product counts equally.
  • Discount depth: The average percentage reduction from full price across products that are on sale.
  • Full-price availability: The share of a brand's products that are both in stock and selling at full price, a proxy for clean, healthy demand.

How each measure is built: methodology.

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Data Purl

Data Purl is an eCommerce pricing and assortment data provider that follows every brand across the retailers that sell it: SKU-level price, discount, availability and assortment history across 400+ retailers back to 2013, compared like for like, with brands resolved to their owners, public or private, and listed owners mapped to tickers.

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