10% premine = 99,999,999.9
first 11,000 blocks
1000 = 11,000,000
next 11,000 blocks
500 = 5,500,000
next 11,000 blocks
250 = 2,750,000
next 2,318 blcoks
150 = 347,700
So really your premine is more like 12% or about 119,597,699.9 coins.
Why wait so long to announce your coin if you already had 10% premined?
Why not start at 0 when you announced the coin instead of mining an additional 20 million coins?