distribute	reads
0-500	0
500-800	1
800-1000	0
1000-1200	1
1200-1400	0
1400-1600	3
1600-1800	1
1800-2000	6
2000-2200	3
2200-2400	3
2400-2600	3
2600-2800	2
2800-3000	1
>3000	40
