distribute	reads
0-500	4157
500-800	2121
800-1000	1238
1000-1200	1433
1200-1400	1678
1400-1600	2110
1600-1800	2984
1800-2000	4234
2000-2200	87285
2200-2400	76316
2400-2600	4541
2600-2800	5258
2800-3000	5396
>3000	186071
