distribute	reads
0-500	47776
500-800	59030
800-1000	19532
1000-1200	13199
1200-1400	9828
1400-1600	7545
1600-1800	6007
1800-2000	5063
2000-2200	4180
2200-2400	3634
2400-2600	3247
2600-2800	2889
2800-3000	2612
>3000	28914
