| Table 2. Estimated stock numbers. | |||||||
| Year\Age | 1 | 2 | 3 | 4 | 5 | 6 | 7+ | 
| 1963 | 452707 | 192529 | 20816 | 10325 | 8393 | 3287 | 1622 | 
| 1964 | 800507 | 138829 | 53316 | 11618 | 5285 | 4605 | 2249 | 
| 1965 | 1060234 | 242802 | 41481 | 23179 | 6352 | 2558 | 3020 | 
| 1966 | 1361367 | 291560 | 69843 | 16591 | 9601 | 3313 | 2867 | 
| 1967 | 1219559 | 362943 | 74533 | 28767 | 7897 | 4715 | 3303 | 
| 1968 | 634759 | 318061 | 92319 | 28424 | 14280 | 3428 | 3514 | 
| 1969 | 557936 | 155749 | 75660 | 34030 | 11268 | 6710 | 3082 | 
| 1970 | 1806677 | 142629 | 40417 | 32370 | 15361 | 4637 | 3948 | 
| 1971 | 2380926 | 447307 | 35102 | 15046 | 15801 | 6715 | 4131 | 
| 1972 | 561856 | 562980 | 94183 | 12193 | 6077 | 6813 | 5612 | 
| 1973 | 832343 | 123377 | 110525 | 29703 | 4983 | 2529 | 4500 | 
| 1974 | 722881 | 182590 | 24101 | 36498 | 10983 | 2183 | 3210 | 
| 1975 | 1256700 | 168890 | 37571 | 9666 | 16372 | 4613 | 2304 | 
| 1976 | 805324 | 288947 | 34372 | 13723 | 3950 | 6859 | 2779 | 
| 1977 | 2061615 | 169736 | 52261 | 10926 | 5259 | 1781 | 4111 | 
| 1978 | 1213477 | 446413 | 31163 | 18710 | 5380 | 2290 | 2279 | 
| 1979 | 1461538 | 259886 | 81879 | 9107 | 7258 | 1780 | 1783 | 
| 1980 | 2433887 | 297747 | 59042 | 24934 | 4036 | 2823 | 1734 | 
| 1981 | 955510 | 480701 | 58983 | 17776 | 9006 | 1656 | 1845 | 
| 1982 | 1636385 | 183506 | 92134 | 17024 | 6661 | 3823 | 1479 | 
| 1983 | 869784 | 313013 | 32893 | 21212 | 5438 | 2439 | 1829 | 
| 1984 | 1656140 | 171957 | 52000 | 8003 | 6747 | 2018 | 1596 | 
| 1985 | 362580 | 328404 | 33124 | 14709 | 2807 | 2602 | 1377 | 
| 1986 | 1797667 | 80258 | 57989 | 10216 | 5518 | 1144 | 1636 | 
| 1987 | 661986 | 383464 | 16146 | 15289 | 3087 | 1990 | 1044 | 
| 1988 | 454067 | 147709 | 69843 | 5134 | 4933 | 1228 | 952 | 
| 1989 | 827364 | 104089 | 30031 | 17256 | 1799 | 1883 | 834 | 
| 1990 | 318380 | 181317 | 19990 | 7799 | 5063 | 631 | 928 | 
| 1991 | 357897 | 74608 | 30577 | 5957 | 2632 | 1928 | 703 | 
| 1992 | 833176 | 87816 | 14618 | 8590 | 1979 | 923 | 861 | 
| 1993 | 392385 | 193687 | 17007 | 4755 | 2693 | 726 | 606 | 
| 1994 | 934718 | 98913 | 34269 | 5154 | 1637 | 950 | 468 | 
| 1995 | 553491 | 228662 | 21493 | 9546 | 1660 | 600 | 483 | 
| 1996 | 338405 | 131926 | 36062 | 5211 | 2940 | 619 | 454 | 
| 1997 | 1168230 | 89232 | 23957 | 8698 | 1739 | 965 | 341 | 
| 1998 | 129832 | 290686 | 19178 | 6510 | 2677 | 614 | 392 | 
| 1999 | 246471 | 34303 | 50312 | 4980 | 1883 | 791 | 394 | 
| 2000 | 467428 | 64926 | 7890 | 9723 | 1364 | 550 | 306 | 
| 2001 | 160653 | 124866 | 13278 | 2091 | 2126 | 308 | 256 | 
| 2002 | 248699 | 45936 | 23813 | 3704 | 547 | 548 | 165 | 
| 2003 | 120934 | 66436 | 9834 | 6680 | 990 | 160 | 202 | 
| 2004 | 212140 | 36461 | 13605 | 2929 | 1824 | 295 | 108 | 
| 2005 | 154045 | 54448 | 7716 | 3362 | 915 | 594 | 129 | 
| 2006 | 366590 | 44891 | 11668 | 2088 | 959 | 308 | 245 | 
| 2007 | 171957 | 98913 | 9398 | 3776 | 846 | 309 | 168 | 
| 2008 | 205048 | 47052 | 21770 | 3004 | 1399 | 376 | 192 | 
| 2009 | 204638 | 54448 | 10782 | 7081 | 1208 | 470 | 190 | 
| 2010 | 322223 | 56557 | 12499 | 3780 | 2717 | 404 | 197 | 
| 2011 | 154508 | 84626 | 13248 | 4260 | 1562 | 1026 | 208 | 
| 2012 | 194658 | 43002 | 20848 | 6177 | 1805 | 656 | 448 | 
| 2013 | 252963 | 48098 | 11662 | 9702 | 3114 | 751 | 464 | 
| 2014 | 348363 | 61513 | 12453 | 5530 | 4993 | 1644 | 631 |