Added some Zetacoin analysis here -
https://bitcointalk.org/index.php?topic=423000.0Was a bit confused about how the block reward got so low so quickly . . .
If you started in August at 1000 per block . . . and we're now in February, that's 5 halvings . . . shouldn't we be at 30/block rather than 2/block?
This is because Zetacoin's difficulty adjustment algorithm is biased towards adjusting difficulty down:
static const int64 nMaxAdjustDown = 20; // 20% adjustment down
static const int64 nMaxAdjustUp = 1; // 1% adjustment up
The effect of this is that average block time over time is less than the target block time.
The logic behind the difficulty algorithm is to prefer adjusting down aggressively when miners leave to prevent getting stuck at high difficulty, i.e.
rather have a faster network with a shorter block times than having a a network stuck at high difficulty and not processing transactions.