distribute	reads
0-500	298
500-800	1324
800-1000	966
1000-1200	1144
1200-1400	1542
1400-1600	2043
1600-1800	2366
1800-2000	2477
2000-2200	2544
2200-2400	2628
2400-2600	2589
2600-2800	2719
2800-3000	2779
>3000	63629
