I think it falls to a quarter of the current amount so 3.4/4 = 0.85. Since this is split between mining and PoS, it is half of that for PoS so 0.425 per stake. This is 1 million coins over a 4 year period I think.

After that it is 1 million coins spread over 5 years (0.34 per stake) , then 1 million over 10 years (.17 per stake)  and then 1 million over 30 years (0.0566 per stake).

So NOW is the time to stock up and to earn as many PoS rewards as you can. These coins are going to be as rare as hens teeth soon.