distribute	reads
0-500	88613
500-800	7241
800-1000	879
1000-1200	296
1200-1400	110
1400-1600	50
1600-1800	18
1800-2000	9
2000-2200	5
2200-2400	2
2400-2600	4
2600-2800	0
2800-3000	1
>3000	0
