| Table 2. Estimated stock numbers. | ||||||
| Year\Age | 0 | 1 | 2 | 3 | 4 | 5+ | 
| 1991 | 148301 | 198392 | 152360 | 45890 | 4360 | 19571 | 
| 1992 | 61636 | 92411 | 108554 | 77964 | 18691 | 13038 | 
| 1993 | 142201 | 38561 | 50262 | 53691 | 31445 | 17480 | 
| 1994 | 215346 | 87466 | 21180 | 24860 | 20576 | 25362 | 
| 1995 | 246471 | 129962 | 45570 | 10589 | 9444 | 23225 | 
| 1996 | 172474 | 148747 | 64667 | 21356 | 4136 | 16523 | 
| 1997 | 146386 | 103985 | 72186 | 29912 | 8189 | 10757 | 
| 1998 | 112758 | 86682 | 51741 | 32016 | 10868 | 10451 | 
| 1999 | 251702 | 66304 | 42702 | 23133 | 11462 | 11891 | 
| 2000 | 222348 | 153891 | 32016 | 18481 | 8289 | 12930 | 
| 2001 | 572633 | 137036 | 71539 | 13089 | 6849 | 12226 | 
| 2002 | 792541 | 369535 | 63259 | 28283 | 4893 | 11076 | 
| 2003 | 850858 | 522301 | 179512 | 26213 | 11180 | 9701 | 
| 2004 | 371759 | 574928 | 264342 | 78747 | 10992 | 13479 | 
| 2005 | 393958 | 253977 | 304066 | 118658 | 35846 | 15251 | 
| 2006 | 400713 | 275681 | 140646 | 138137 | 55548 | 32435 | 
| 2007 | 438888 | 278730 | 149941 | 67037 | 63133 | 53637 | 
| 2008 | 494350 | 301945 | 149044 | 71682 | 32403 | 67982 | 
| 2009 | 721437 | 343176 | 155127 | 72839 | 35846 | 60658 | 
| 2010 | 897169 | 503329 | 171957 | 75660 | 37609 | 61206 | 
| 2011 | 1115708 | 636666 | 253977 | 84204 | 39222 | 66039 | 
| 2012 | 668639 | 794128 | 331042 | 129832 | 44002 | 73497 | 
| 2013 | 1551915 | 481663 | 418319 | 172301 | 69913 | 83366 | 
| 2014 | 753135 | 1154295 | 264342 | 217075 | 93714 | 108337 | 
| 2015 | 632857 | 549080 | 647582 | 138413 | 116076 | 139665 | 
| 2016 | 483594 | 464632 | 299839 | 342491 | 74161 | 178796 |