distribute	reads
0-500	25
500-800	12
800-1000	1
1000-1200	0
1200-1400	0
1400-1600	0
1600-1800	3
1800-2000	5
2000-2200	2
2200-2400	7
2400-2600	3
2600-2800	7
2800-3000	2
>3000	4
