distribute	reads
0-500	0
500-800	0
800-1000	0
1000-1200	2
1200-1400	0
1400-1600	7
1600-1800	1
1800-2000	11
2000-2200	23
2200-2400	41
2400-2600	92
2600-2800	145
2800-3000	210
>3000	3176
