| Table 3. Estimated stock numbers at age. | |||||||
| Year Age | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 
| 1981 | 9807 | 20595 | 7215 | 2092 | 508 | 73 | 608 | 
| 1982 | 23263 | 5140 | 8028 | 2716 | 840 | 228 | 531 | 
| 1983 | 14372 | 11975 | 2234 | 2929 | 1037 | 337 | 550 | 
| 1984 | 22756 | 6534 | 4785 | 809 | 1044 | 391 | 585 | 
| 1985 | 10729 | 11224 | 2372 | 1542 | 273 | 348 | 608 | 
| 1986 | 18903 | 4509 | 4065 | 739 | 436 | 90 | 558 | 
| 1987 | 45627 | 9707 | 1714 | 1359 | 247 | 140 | 444 | 
| 1988 | 7386 | 19832 | 3609 | 532 | 406 | 80 | 387 | 
| 1989 | 20433 | 2945 | 6369 | 1161 | 179 | 131 | 333 | 
| 1990 | 8808 | 9186 | 989 | 1743 | 371 | 57 | 299 | 
| 1991 | 12078 | 3516 | 3272 | 356 | 531 | 137 | 267 | 
| 1992 | 20628 | 4995 | 1061 | 1071 | 129 | 161 | 272 | 
| 1993 | 7128 | 9047 | 1701 | 303 | 334 | 46 | 283 | 
| 1994 | 13594 | 3248 | 3150 | 510 | 103 | 111 | 227 | 
| 1995 | 9333 | 5876 | 1189 | 1058 | 158 | 36 | 203 | 
| 1996 | 3723 | 4189 | 1795 | 378 | 342 | 54 | 162 | 
| 1997 | 14091 | 1666 | 1290 | 491 | 117 | 116 | 138 | 
| 1998 | 5011 | 6580 | 485 | 357 | 143 | 36 | 153 | 
| 1999 | 3509 | 1959 | 1862 | 130 | 105 | 47 | 134 | 
| 2000 | 11801 | 1476 | 532 | 506 | 38 | 32 | 124 | 
| 2001 | 3550 | 4939 | 463 | 162 | 168 | 12 | 101 | 
| 2002 | 6054 | 1471 | 1530 | 135 | 44 | 53 | 78 | 
| 2003 | 2058 | 2420 | 414 | 465 | 43 | 13 | 73 | 
| 2004 | 2760 | 804 | 641 | 104 | 140 | 15 | 56 | 
| 2005 | 1718 | 1040 | 219 | 181 | 32 | 40 | 43 | 
| 2006 | 6641 | 655 | 342 | 54 | 51 | 10 | 48 | 
| 2007 | 2067 | 3014 | 212 | 110 | 12 | 16 | 38 | 
| 2008 | 1449 | 759 | 1017 | 60 | 37 | 4 | 34 | 
| 2009 | 5019 | 635 | 282 | 264 | 18 | 15 | 24 | 
| 2010 | 5059 | 2368 | 271 | 78 | 64 | 4 | 24 | 
| 2011 | 2285 | 2403 | 912 | 78 | 26 | 24 | 20 | 
| 2012 | 4118 | 1065 | 1053 | 260 | 23 | 9 | 28 | 
| 2013 | 7142 | 1795 | 520 | 414 | 88 | 8 | 27 | 
| 2014 | 5647 | 3270 | 797 | 217 | 173 | 32 | 24 | 
| 2015 | 4947 | 2508 | 1523 | 309 | 96 | 79 | 37 | 
| 2016 | 2295 | 2457 | 1125 | 664 | 129 | 43 | 77 | 
| 2017 | 1649 | 1010 | 1252 | 482 | 296 | 56 | 85 | 
| 2018 | 1321 | 781 | 402 | 503 | 194 | 124 | 99 | 
| 2019 | 2692 | 558 | 320 | 137 | 179 | 68 | 141 |