distribute	reads
0-500	319558
500-800	18609
800-1000	1541
1000-1200	341
1200-1400	80
1400-1600	28
1600-1800	6
1800-2000	2
2000-2200	0
2200-2400	1
2400-2600	0
2600-2800	0
2800-3000	0
>3000	1
