distribute	reads
0-500	46282
500-800	13465
800-1000	6446
1000-1200	5547
1200-1400	4895
1400-1600	4212
1600-1800	3717
1800-2000	3407
2000-2200	2933
2200-2400	2671
2400-2600	2450
2600-2800	2276
2800-3000	1961
>3000	29883
