distribute	reads
0-500	3331
500-800	1504
800-1000	1370
1000-1200	2236
1200-1400	3692
1400-1600	5248
1600-1800	6638
1800-2000	7488
2000-2200	7783
2200-2400	7289
2400-2600	6511
2600-2800	5481
2800-3000	4411
>3000	11822
