distribute	reads
0-500	1452
500-800	974
800-1000	310
1000-1200	200
1200-1400	102
1400-1600	47
1600-1800	20
1800-2000	11
2000-2200	8
2200-2400	2
2400-2600	2
2600-2800	1
2800-3000	0
>3000	5
