The 30th Index

How the 30th Index is worked out

Which products count?

Every sealed 30th Celebration product that is out in the UK and has at least 5 usable eBay listings that day. Older sets are shown on the site for comparison but are never part of the index.

What is the eBay figure?

The average of the cheapest 5 current eBay UK listings for each product, price plus postage, one listing per seller. These are asking prices on live listings, not prices anything has sold for. Listings that are not the sealed product are removed first: single cards, lots, pre-orders, empty, opened or damaged boxes, accessories, non-English products, and anything priced far below the other listings.

What is the shop price?

The cheapest UK shop price we have confirmed for each product, whether or not it is in stock. There is no single official UK price, so we use the lowest real one rather than a quoted RRP.

How is the index calculated?

For each product, the markup is the eBay figure against the shop price, as a percentage. The index is the plain average of those markups, rounded to a whole number. It is recalculated every morning.

Has the history been corrected?

Yes, twice, and both times the corrected figures came from the same day's stored listings. On 30 September 2026 we found listings that were not sealed products (an empty display case, boxes with the packs removed, promo-only sets) in the cheapest five on some days. On 5 October 2026 we found Booster Bundle figures counting lots of loose packs, and boxes with torn or ripped seals counted as sealed. In both cases the rules were tightened, the history was recalculated without those listings, and days with nothing genuine left were left blank rather than estimated.