distribute	reads
0-500	3585
500-800	2174
800-1000	1299
1000-1200	1384
1200-1400	1666
1400-1600	2049
1600-1800	3011
1800-2000	4560
2000-2200	6847
2200-2400	10178
2400-2600	14209
2600-2800	18342
2800-3000	22106
>3000	378618
