distribute	reads
0-500	4506
500-800	11590
800-1000	7393
1000-1200	7013
1200-1400	6061
1400-1600	5422
1600-1800	4892
1800-2000	4396
2000-2200	3963
2200-2400	3788
2400-2600	3394
2600-2800	2977
2800-3000	2889
>3000	38747
