distribute	reads
0-500	7074
500-800	20416
800-1000	13191
1000-1200	11763
1200-1400	10088
1400-1600	9197
1600-1800	7895
1800-2000	7399
2000-2200	6468
2200-2400	6083
2400-2600	5347
2600-2800	4998
2800-3000	4700
>3000	60840
