distribute	reads
0-500	6284
500-800	5229
800-1000	4213
1000-1200	4634
1200-1400	4787
1400-1600	5179
1600-1800	5492
1800-2000	5689
2000-2200	6377
2200-2400	7305
2400-2600	8590
2600-2800	10182
2800-3000	12286
>3000	370688
