A key indicator to the robustness of a Proof-of-Stake system is the staking ratio of the network. A high staking ratio will make the system hard-to-attack. However, once the staking ratio pass a point where it becomes too high, the system will be overwhelmed, consequently, liquidity in the system will be decreased. Therefore, in the long run, the staking ratio will dynamically adjust itself to reach equilibrium. Referring to current PoS public blockchains, the equilibrium point should be where the staking ratio is between 0.5 and 0.6.