distribute	reads
0-500	4933
500-800	6485
800-1000	3813
1000-1200	3440
1200-1400	3098
1400-1600	2761
1600-1800	2421
1800-2000	2176
2000-2200	1969
2200-2400	1774
2400-2600	1780
2600-2800	1462
2800-3000	1446
>3000	18571
