Guys and girls. I really hate to drop a bomb like this, but sooner or later it will get discussed anyway.
Have you seen block height? Currently we are going on the rate of 1.5 times the daily block count target. For example. Mintcoin with 30sec block target shoud generate 2880 blocks per 24hours. The real result for last 24 hours is about 1.5 times higher. And earlier days are similar.
What it means?
Since all PoW/PoS hybrid coins have interest targets calculated based on nHeight (block number), it means that we will hit the second year interest rate much sooner than 1 year since beginning.

Why this is happening?
Blockchain has more blocks because PoS blocks dont follow original PoW difficulty formula. First 20 days were OK ,because there was no PoS. Since day 20, average daily block rate count has steadily raised.

Remember. This is not only Mintcoin issue. Its an issue of all PoS hybrid coins. Its not harmful in any way, but it just moves all yearly targets a lot closer than written in OP.