| Table 3. Estimated stock numbers at age. | ||||||
| Year Age | 1 | 2 | 3 | 4 | 5 | 6 |
| 1997 | 13257 | 6227 | 8475 | 1287 | 300 | 125 |
| 1998 | 12602 | 10717 | 2666 | 2560 | 360 | 103 |
| 1999 | 9704 | 8148 | 5271 | 624 | 541 | 97 |
| 2000 | 7039 | 7485 | 3336 | 1353 | 154 | 133 |
| 2001 | 5549 | 3599 | 2624 | 778 | 242 | 59 |
| 2002 | 8400 | 2977 | 1250 | 548 | 122 | 56 |
| 2003 | 1653 | 4365 | 835 | 263 | 115 | 30 |
| 2004 | 8865 | 1287 | 1637 | 260 | 89 | 59 |
| 2005 | 3130 | 4368 | 238 | 314 | 48 | 28 |
| 2006 | 4254 | 2090 | 1409 | 81 | 90 | 26 |
| 2007 | 1328 | 2047 | 572 | 332 | 30 | 47 |
| 2008 | 463 | 318 | 214 | 80 | 61 | 18 |
| 2009 | 1364 | 159 | 58 | 50 | 23 | 14 |
| 2010 | 1324 | 781 | 63 | 22 | 15 | 9 |
| 2011 | 1813 | 788 | 301 | 30 | 11 | 7 |
| 2012 | 3271 | 752 | 185 | 123 | 20 | 10 |
| 2013 | 4126 | 1799 | 416 | 130 | 60 | 17 |
| 2014 | 1578 | 3036 | 860 | 316 | 112 | 53 |
| 2015 | 952 | 679 | 1486 | 730 | 282 | 129 |
| 2016 | 110 | 389 | 382 | 789 | 522 | 238 |
| 2017 | 2067 | 129 | 216 | 178 | 398 | 270 |
| 2018 | 204 | 827 | 28 | 106 | 88 | 334 |