| Table 3. Estimated stock numbers at age. | ||||||
| Year Age | 0 | 1 | 2 | 3 | 4 | 5 | 
| 1991 | 151997 | 188360 | 138725 | 41654 | 3841 | 16068 | 
| 1992 | 60336 | 97599 | 92643 | 69492 | 17604 | 10522 | 
| 1993 | 143547 | 38856 | 47834 | 45972 | 29045 | 14785 | 
| 1994 | 213988 | 91025 | 18280 | 22650 | 17847 | 21850 | 
| 1995 | 242839 | 133651 | 40831 | 8311 | 8373 | 19163 | 
| 1996 | 163911 | 150335 | 57481 | 17804 | 2966 | 13027 | 
| 1997 | 153672 | 102111 | 64265 | 24835 | 6322 | 7575 | 
| 1998 | 115368 | 95655 | 43048 | 27180 | 8673 | 6597 | 
| 1999 | 248986 | 72164 | 39863 | 17911 | 9319 | 7173 | 
| 2000 | 183245 | 155828 | 28924 | 15713 | 5763 | 7430 | 
| 2001 | 536990 | 114839 | 59776 | 10742 | 4782 | 5761 | 
| 2002 | 688554 | 338848 | 42906 | 21152 | 3080 | 4406 | 
| 2003 | 768402 | 448783 | 137159 | 16423 | 6665 | 3274 | 
| 2004 | 287353 | 519161 | 199639 | 57728 | 5869 | 4660 | 
| 2005 | 355232 | 199575 | 246554 | 88123 | 21581 | 4901 | 
| 2006 | 379531 | 251169 | 99654 | 113842 | 34516 | 12418 | 
| 2007 | 417678 | 265827 | 120052 | 43898 | 41492 | 20190 | 
| 2008 | 473949 | 289273 | 121116 | 50843 | 15467 | 25002 | 
| 2009 | 672707 | 324262 | 124348 | 49215 | 17552 | 16253 | 
| 2010 | 770401 | 461725 | 138644 | 51008 | 17738 | 14331 | 
| 2011 | 917012 | 535883 | 203301 | 58752 | 19383 | 14453 | 
| 2012 | 528567 | 649627 | 249362 | 90961 | 23770 | 16159 | 
| 2013 | 1438531 | 379237 | 312077 | 114143 | 37412 | 19148 | 
| 2014 | 700925 | 1042552 | 188464 | 146125 | 47407 | 27036 | 
| 2015 | 538016 | 509135 | 519989 | 88060 | 59300 | 34378 | 
| 2016 | 339077 | 387473 | 243096 | 232693 | 33544 | 40450 | 
| 2017 | 480817 | 240519 | 171917 | 101131 | 81580 | 29600 |