distribute	reads
0-500	32677
500-800	17793
800-1000	7565
1000-1200	5862
1200-1400	4457
1400-1600	3708
1600-1800	3257
1800-2000	2856
2000-2200	2477
2200-2400	2147
2400-2600	1989
2600-2800	1816
2800-3000	1639
>3000	39091
