distribute	reads
0-500	21
500-800	4
800-1000	0
1000-1200	0
1200-1400	2
1400-1600	11
1600-1800	19
1800-2000	17
2000-2200	16
2200-2400	40
2400-2600	14
2600-2800	21
2800-3000	7
>3000	108
