distribute	reads
0-500	584
500-800	1913
800-1000	1307
1000-1200	1502
1200-1400	1817
1400-1600	2097
1600-1800	2323
1800-2000	2405
2000-2200	2435
2200-2400	2351
2400-2600	2396
2600-2800	2350
2800-3000	2298
>3000	81828
