distribute	reads
0-500	16726
500-800	2600
800-1000	1408
1000-1200	1681
1200-1400	2501
1400-1600	4298
1600-1800	7191
1800-2000	11256
2000-2200	16994
2200-2400	23320
2400-2600	28499
2600-2800	32755
2800-3000	36744
>3000	337223
