distribute	reads
0-500	93726
500-800	11675
800-1000	1297
1000-1200	375
1200-1400	117
1400-1600	45
1600-1800	15
1800-2000	2
2000-2200	2
2200-2400	0
2400-2600	0
2600-2800	0
2800-3000	0
>3000	0
