It's around 5-6% interest currently, so around 50-60 blk per year. Just keep in mind that the inflation rate of the network is under 1%, so as long as you're staking your total percentage holding of the network is going up (i.e. if you hold 1% of the network and stake for a year you would have around 1.04% of the network). PoS 2.0+ coins will be extremely competitive versus a 0% inflation rate in the long run.