distribute	reads
0-500	10
500-800	5
800-1000	5
1000-1200	0
1200-1400	0
1400-1600	0
1600-1800	4
1800-2000	3
2000-2200	2
2200-2400	6
2400-2600	5
2600-2800	3
2800-3000	3
>3000	33
