Relating to staking, and stakers, to earn profits from their investments in Proof-of-Stake coins (mostly have masternodes), stakers should remember that they have to pay their attention on inflation rate, and schedule of inflational changes over different phases of block number. They have to observe those schedules very carefully to make their periodically cashing out and waiting dumps of cheap coins to buy their interest coins back. Such PoS coins usually are dumped and pumped at important block numbers at which inflation rates change.