According to the Staking Rewards, the Staking Market Cap (valuation of all projects that have a staking mechanism) is currently at 68.2 Billion USD.
We have prepared the list of projects sorted by the USD value of the staked tokens. According to the list, the top 5: Ethereum, Cardano, BNB, Solana, and Polkadot.
We calculated the ratio of staked coins to the circulating supply as well. The leaders are Mina Protocol (98.8%), Oasis Network (96.9%), Curve DAO (96.3%), Aleph Zero (95.5%), and Casper Network (80.6%).