distribute	reads
0-500	48654
500-800	34199
800-1000	15750
1000-1200	11571
1200-1400	8780
1400-1600	7023
1600-1800	5684
1800-2000	4803
2000-2200	3906
2200-2400	3438
2400-2600	2959
2600-2800	2650
2800-3000	2266
>3000	53014
