distribute	reads
0-500	3646
500-800	2170
800-1000	1653
1000-1200	1912
1200-1400	2289
1400-1600	3575
1600-1800	6113
1800-2000	9984
2000-2200	15183
2200-2400	20980
2400-2600	26869
2600-2800	31158
2800-3000	32710
>3000	155777
