You can see the ideal staking rate on polkadot.js. If you open Network > Staking > Overview
With the runtime upgrade v1.0.0 the ideal staking rate was changed to 75% minus the amount of all active Parachains (that are not System Parachains) capped to a maximum of 60 Parachains, so the staking rate moves between 75% and 55% (on Polkadot, 45% on Kusama). But with the upcoming changes, it is something that needs to be reconsidered and changed via governance.