Seems like a fair heuristic, it isn't the parameters of the PoS though. The actual stake depends on how many other coins are staking along with yours.
can you explain more please
From the opening post:
SPECIFICATIONS
Consensus: POS (from block 12500); Blocktime: 60 seconds; Block reward: 1 STRAT
So Stratis uses Proof of Stake as consensus method. This means that by staking your coins, you are helping to secure the network.To do this you have to hold your Stratis in the wallet and have it open and unlocked for staking. The bigger your stake (the more STRAT you hold), the more rewards you will receive, depending on how many others are currently staking their Stratis coins at that moment.
You can read more here:
https://en.bitcoin.it/wiki/Proof_of_Stake