distribute	reads
0-500	93992
500-800	48980
800-1000	26001
1000-1200	23542
1200-1400	20729
1400-1600	18492
1600-1800	16240
1800-2000	14894
2000-2200	13169
2200-2400	12050
2400-2600	11064
2600-2800	9873
2800-3000	9269
>3000	119617
