How much of English Pokémon card-set lists is 'secret' cards numbered beyond the set total

What this is

How much of English Pokémon card-set lists is 'secret' cards numbered beyond the set total: 2.15% for sets from 1999 to 2017, 16.1% for regular sets 2018–2026 and 28.49% for special sets.

How it’s built

1. Took printed and secret card counts for every English set from Bulbapedia, a fan encyclopedia.
2. Pooled by period and type: before 2018, 190 secret against 8,663 printed; regular sets 2018–2026, 1,178 against 6,141; special sets, 559 against 1,403.
3. Repeated with numbered subsets (such as Trainer Gallery) counted as chase cards: 4.21%, 17.45% and 38.28%.

What we assumed

• Bulbapedia's counts are right.A fan source, but set totals are printed on the cards and widely published.
• Secret cards stand for the rare 'chase' layer.The base case; subsets are added as a sensitivity because they are rare pulls too.

Sanity check

Regular sets climbed in steps: 2.14% before 2018, 9.61% in 2018–2022, 25.31% in 2023–2026. Two 2026 sets have secret counts still to be announced.

Where it comes from

Our calculation from other figures in the trainer’s notes:

• EstimateEn median set size and secret share by era bulbapedia, 1999-2026 (to Delta Reign, 6 November 2026)