If one does simple math:
 61.5% chance of the reward being 1 TTY
20% chance of the reward being 2 TTY
10% chance of the reward being 5 TTY
5% chance of the reward being 10 TTY
2.5% chance of the reward being 20 TTY
1% chance of the reward being 50 TTY

100 % chance  would pay out 88 TTY this would be 88TTY / 6 different chances = 14.66 say 15 per block on average. Total Blocks: 1,680,000*15= 25,200,000 coins.
25,2 mil. coins