distribute	reads
0-500	9888
500-800	7924
800-1000	3445
1000-1200	2636
1200-1400	2062
1400-1600	1699
1600-1800	1286
1800-2000	1071
2000-2200	875
2200-2400	757
2400-2600	636
2600-2800	484
2800-3000	428
>3000	2961
