| Table 2. Estimated stock numbers. | |||||||
| Year\Age | 2 | 3 | 4 | 5 | 6 | 7 | 8+ | 
| 1966 | 383464 | 232118 | 71898 | 21539 | 4434 | 1831 | 162 | 
| 1967 | 371759 | 269144 | 95225 | 26213 | 6560 | 1081 | 488 | 
| 1968 | 337392 | 258590 | 108120 | 33423 | 7767 | 1070 | 253 | 
| 1969 | 299240 | 233748 | 106085 | 35846 | 8776 | 2045 | 348 | 
| 1970 | 256273 | 205253 | 97538 | 37911 | 8818 | 2498 | 685 | 
| 1971 | 268069 | 176663 | 88965 | 34926 | 10410 | 2604 | 943 | 
| 1972 | 326440 | 188151 | 81961 | 32728 | 9688 | 3968 | 1347 | 
| 1973 | 399113 | 231191 | 88168 | 29912 | 9666 | 3652 | 2033 | 
| 1974 | 407176 | 290977 | 114234 | 32827 | 9050 | 3661 | 2169 | 
| 1975 | 330050 | 302852 | 147709 | 45297 | 10929 | 3365 | 2179 | 
| 1976 | 324811 | 244752 | 154045 | 60355 | 16544 | 4106 | 2094 | 
| 1977 | 429338 | 247212 | 132191 | 62505 | 20933 | 5547 | 2089 | 
| 1978 | 673336 | 332369 | 145510 | 58747 | 21699 | 6862 | 2499 | 
| 1979 | 593623 | 515555 | 199786 | 70757 | 23179 | 8805 | 3814 | 
| 1980 | 482627 | 441971 | 306815 | 97052 | 30152 | 9526 | 5159 | 
| 1981 | 606828 | 357897 | 258332 | 140646 | 37722 | 11834 | 5749 | 
| 1982 | 609260 | 459089 | 215561 | 114348 | 51175 | 12956 | 6075 | 
| 1983 | 447754 | 452707 | 273758 | 96664 | 40579 | 16747 | 6185 | 
| 1984 | 317744 | 324162 | 263550 | 122639 | 34648 | 14136 | 8036 | 
| 1985 | 274306 | 226840 | 176310 | 110968 | 42404 | 11099 | 7098 | 
| 1986 | 263024 | 192914 | 121540 | 69633 | 38254 | 13498 | 5794 | 
| 1987 | 289237 | 188339 | 103466 | 45297 | 21455 | 10049 | 5077 | 
| 1988 | 195243 | 204230 | 97538 | 38216 | 14059 | 6013 | 4236 | 
| 1989 | 114462 | 137448 | 98125 | 33691 | 12192 | 4409 | 3209 | 
| 1990 | 98223 | 81552 | 61821 | 28999 | 9108 | 3740 | 2345 | 
| 1991 | 93807 | 68186 | 36316 | 16779 | 6292 | 2434 | 1638 | 
| 1992 | 140505 | 67037 | 29852 | 10147 | 3204 | 1389 | 897 | 
| 1993 | 173338 | 103985 | 36098 | 11223 | 2732 | 853 | 606 | 
| 1994 | 143918 | 129185 | 61084 | 17863 | 4177 | 1213 | 648 | 
| 1995 | 127134 | 105240 | 73277 | 29762 | 7041 | 1788 | 803 | 
| 1996 | 109864 | 93526 | 57526 | 32306 | 10387 | 2644 | 964 | 
| 1997 | 91126 | 80660 | 48243 | 21899 | 8472 | 3851 | 1350 | 
| 1998 | 127899 | 68118 | 40175 | 17710 | 4862 | 2775 | 1709 | 
| 1999 | 123377 | 95990 | 35207 | 14131 | 3798 | 1616 | 1497 | 
| 2000 | 118302 | 91675 | 48533 | 11420 | 2558 | 1229 | 1012 | 
| 2001 | 95511 | 87291 | 42959 | 12591 | 1497 | 590 | 516 | 
| 2002 | 101417 | 70969 | 39066 | 8468 | 1348 | 171 | 127 | 
| 2003 | 54830 | 75963 | 30122 | 8099 | 1175 | 296 | 65 | 
| 2004 | 57240 | 41151 | 31603 | 4560 | 1089 | 256 | 79 | 
| 2005 | 105240 | 43088 | 16468 | 4803 | 433 | 189 | 58 | 
| 2006 | 99310 | 80258 | 17401 | 3159 | 936 | 146 | 84 | 
| 2007 | 97149 | 75132 | 34892 | 3970 | 682 | 336 | 82 | 
| 2008 | 124991 | 73718 | 35137 | 7709 | 866 | 172 | 106 | 
| 2009 | 118658 | 97149 | 36461 | 7007 | 1422 | 228 | 73 | 
| 2010 | 135402 | 91675 | 51328 | 6537 | 1524 | 384 | 82 | 
| 2011 | 141492 | 106617 | 49762 | 7502 | 870 | 245 | 75 | 
| 2012 | 126754 | 111860 | 59814 | 8006 | 1508 | 265 | 97 | 
| 2013 | 162267 | 100208 | 63895 | 8585 | 1151 | 364 | 87 | 
| 2014 | 174556 | 129314 | 59278 | 9670 | 991 | 279 | 109 |