distribute	reads
0-500	13
500-800	10
800-1000	4
1000-1200	3
1200-1400	1
1400-1600	2
1600-1800	8
1800-2000	2
2000-2200	14
2200-2400	10
2400-2600	17
2600-2800	19
2800-3000	24
>3000	1243
