distribute	reads
0-500	53
500-800	19
800-1000	3
1000-1200	2
1200-1400	3
1400-1600	1
1600-1800	0
1800-2000	0
2000-2200	1
2200-2400	2
2400-2600	0
2600-2800	2
2800-3000	0
>3000	86
