How many blocks will Cosmos-SDK calculate validator set again and where is the code

I can only find cosmos will select top 100 validator in the first year and than grow 13% each next year from office document, but I do not know how many blocks will validator set recalculate, and where is the implement code, Can anyone tell me ? really thanks!

It’s not implemented in the code but it’s decided with governance proposal right now, for example you can look at this proposal https://hubble.figment.network/cosmos/chains/cosmoshub-2/governance/proposals/10 that sets validator number to 125 and since it’s passed with the next upgrade will go live