distribute	reads
0-500	718
500-800	1830
800-1000	1602
1000-1200	2233
1200-1400	2999
1400-1600	3364
1600-1800	3309
1800-2000	3395
2000-2200	3070
2200-2400	2912
2400-2600	2843
2600-2800	2624
2800-3000	2491
>3000	27006
