For example today is March 9, and bitcoin price is around $83K. Exactly 4 years ago, it was around $52.5K. So current price is higher than the price 4 years ago.

So for each moment, from now till the end of year, we look if the price of bitcoin is higher or lower than the price exactly 4 years before the observed moment.

For example for July 1st, we compare the price with the price on July 1st 2021, etc...

If at any moment in this year, the price of bitcoin goes below the price 4 years before that moment, this resolves as YES, otherwise, this resolves as NO.

This resolves as NO, on January 1st 2026, if the price never falls below the price 4 years earlier.

It resolves as YES as soon as the price of bitcoin falls below the price exactly 4 years before the observed moment.