| Table 3. Estimated stock numbers at age. | |||||||
| Year Age | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
| 1981 | 10374 | 19939 | 7015 | 1975 | 468 | 63 | 51 |
| 1982 | 24070 | 5268 | 7805 | 2575 | 731 | 186 | 45 |
| 1983 | 14097 | 12019 | 2215 | 2775 | 896 | 260 | 84 |
| 1984 | 24003 | 6571 | 4714 | 779 | 882 | 296 | 113 |
| 1985 | 10494 | 11504 | 2436 | 1493 | 231 | 254 | 122 |
| 1986 | 21004 | 4609 | 4167 | 747 | 376 | 65 | 101 |
| 1987 | 45001 | 10223 | 1750 | 1331 | 216 | 105 | 48 |
| 1988 | 7222 | 19560 | 3750 | 533 | 354 | 62 | 44 |
| 1989 | 21603 | 3015 | 6383 | 1152 | 157 | 100 | 32 |
| 1990 | 8314 | 9483 | 1035 | 1716 | 324 | 44 | 37 |
| 1991 | 11965 | 3438 | 3347 | 348 | 477 | 104 | 26 |
| 1992 | 21419 | 5014 | 1080 | 1026 | 111 | 133 | 39 |
| 1993 | 7548 | 9313 | 1708 | 301 | 293 | 35 | 53 |
| 1994 | 13757 | 3393 | 3246 | 488 | 90 | 86 | 27 |
| 1995 | 9993 | 5991 | 1226 | 1002 | 136 | 27 | 33 |
| 1996 | 4154 | 4425 | 1889 | 361 | 293 | 41 | 18 |
| 1997 | 16866 | 1825 | 1395 | 494 | 104 | 87 | 17 |
| 1998 | 5436 | 7518 | 544 | 362 | 139 | 30 | 30 |
| 1999 | 4163 | 2201 | 2160 | 138 | 103 | 43 | 18 |
| 2000 | 14246 | 1754 | 629 | 555 | 38 | 29 | 18 |
| 2001 | 4131 | 5913 | 544 | 171 | 160 | 11 | 14 |
| 2002 | 6928 | 1692 | 1818 | 146 | 43 | 43 | 7 |
| 2003 | 2297 | 2745 | 482 | 494 | 40 | 11 | 13 |
| 2004 | 3144 | 893 | 750 | 113 | 130 | 11 | 6 |
| 2005 | 2119 | 1209 | 253 | 188 | 29 | 31 | 4 |
| 2006 | 7012 | 846 | 399 | 58 | 44 | 7 | 9 |
| 2007 | 2498 | 3022 | 284 | 105 | 12 | 10 | 4 |
| 2008 | 1721 | 989 | 1078 | 71 | 25 | 3 | 3 |
| 2009 | 5221 | 723 | 349 | 256 | 15 | 6 | 1 |
| 2010 | 5943 | 2298 | 271 | 78 | 51 | 3 | 2 |
| 2011 | 2179 | 2649 | 872 | 62 | 16 | 11 | 1 |
| 2012 | 4100 | 972 | 1076 | 203 | 12 | 4 | 3 |
| 2013 | 7134 | 1775 | 453 | 322 | 48 | 3 | 2 |
| 2014 | 5936 | 3216 | 759 | 148 | 87 | 12 | 1 |
| 2015 | 5250 | 2670 | 1486 | 237 | 45 | 28 | 4 |
| 2016 | 2282 | 2484 | 1194 | 516 | 72 | 15 | 10 |