distribute	reads
0-500	3672
500-800	5048
800-1000	2890
1000-1200	2559
1200-1400	2290
1400-1600	1948
1600-1800	1808
1800-2000	1639
2000-2200	1541
2200-2400	1360
2400-2600	1223
2600-2800	1082
2800-3000	1057
>3000	14933
