distribute	reads
0-500	7754
500-800	13814
800-1000	8273
1000-1200	7268
1200-1400	6638
1400-1600	5792
1600-1800	5282
1800-2000	4795
2000-2200	4325
2200-2400	3851
2400-2600	3686
2600-2800	3279
2800-3000	3052
>3000	42942
