| Table 2. Estimated stock numbers. | |||||||
| Year\Age | 1 | 2 | 3 | 4 | 5 | 6 | 7+ | 
| 1963 | 473544 | 186093 | 21729 | 10347 | 8615 | 3299 | 1642 | 
| 1964 | 869784 | 140505 | 52365 | 11659 | 5325 | 4628 | 2328 | 
| 1965 | 1047587 | 249696 | 40660 | 22834 | 6343 | 2633 | 3168 | 
| 1966 | 1386094 | 281813 | 69633 | 16679 | 9890 | 3320 | 2925 | 
| 1967 | 1278247 | 361494 | 72839 | 29144 | 7887 | 4791 | 3249 | 
| 1968 | 678066 | 322223 | 90672 | 27723 | 14158 | 3490 | 3567 | 
| 1969 | 610480 | 162267 | 76573 | 33725 | 11271 | 6591 | 3123 | 
| 1970 | 1781560 | 147561 | 40015 | 31984 | 15221 | 4781 | 4093 | 
| 1971 | 2338453 | 431059 | 35242 | 14946 | 15357 | 6808 | 4197 | 
| 1972 | 584201 | 552937 | 92781 | 12275 | 6107 | 6640 | 5385 | 
| 1973 | 862853 | 129573 | 110636 | 29231 | 4960 | 2509 | 4553 | 
| 1974 | 806130 | 193881 | 25848 | 37012 | 11034 | 2145 | 3142 | 
| 1975 | 1321133 | 180954 | 39656 | 9639 | 16205 | 4609 | 2270 | 
| 1976 | 807744 | 298941 | 36026 | 13691 | 3970 | 6798 | 2783 | 
| 1977 | 2028891 | 176134 | 55437 | 11340 | 5321 | 1731 | 4027 | 
| 1978 | 1282087 | 458172 | 32728 | 18697 | 5179 | 2263 | 2291 | 
| 1979 | 1411269 | 286072 | 84036 | 9366 | 7168 | 1811 | 1797 | 
| 1980 | 2195675 | 310209 | 61821 | 25084 | 4029 | 2825 | 1687 | 
| 1981 | 885582 | 479261 | 61574 | 17845 | 9191 | 1631 | 1831 | 
| 1982 | 1376425 | 188339 | 94372 | 16928 | 6681 | 3756 | 1432 | 
| 1983 | 801307 | 290686 | 34098 | 21222 | 5447 | 2430 | 1816 | 
| 1984 | 1349170 | 172646 | 54666 | 8135 | 6843 | 2022 | 1582 | 
| 1985 | 379269 | 297450 | 35383 | 15420 | 2900 | 2646 | 1383 | 
| 1986 | 1608801 | 85819 | 60536 | 10329 | 5634 | 1160 | 1630 | 
| 1987 | 652783 | 372503 | 17829 | 15587 | 3231 | 2011 | 1033 | 
| 1988 | 454067 | 153123 | 72330 | 5295 | 5031 | 1245 | 990 | 
| 1989 | 710696 | 107474 | 31603 | 17401 | 1806 | 1891 | 832 | 
| 1990 | 324811 | 169906 | 21114 | 7886 | 5074 | 639 | 944 | 
| 1991 | 350109 | 79937 | 32565 | 5989 | 2615 | 1914 | 672 | 
| 1992 | 714973 | 88433 | 16212 | 8701 | 1968 | 929 | 871 | 
| 1993 | 404335 | 186093 | 18886 | 5013 | 2795 | 737 | 628 | 
| 1994 | 802912 | 104925 | 37760 | 5387 | 1695 | 993 | 485 | 
| 1995 | 492870 | 214701 | 23742 | 10231 | 1744 | 632 | 517 | 
| 1996 | 364397 | 131531 | 41606 | 5746 | 3174 | 645 | 461 | 
| 1997 | 909818 | 99409 | 27750 | 9563 | 1879 | 1037 | 363 | 
| 1998 | 159851 | 252206 | 22181 | 6928 | 2824 | 651 | 431 | 
| 1999 | 278452 | 42916 | 52628 | 5197 | 1966 | 827 | 393 | 
| 2000 | 494350 | 77575 | 10163 | 10427 | 1442 | 600 | 345 | 
| 2001 | 204434 | 142629 | 17654 | 2394 | 2454 | 364 | 295 | 
| 2002 | 243531 | 58513 | 33090 | 4355 | 651 | 661 | 198 | 
| 2003 | 137036 | 68872 | 13899 | 8164 | 1178 | 190 | 245 | 
| 2004 | 194853 | 39975 | 16272 | 3346 | 2102 | 334 | 122 | 
| 2005 | 151448 | 54666 | 9483 | 3454 | 969 | 630 | 135 | 
| 2006 | 301945 | 44046 | 13474 | 2177 | 953 | 303 | 239 | 
| 2007 | 141775 | 90944 | 11126 | 3704 | 856 | 311 | 168 | 
| 2008 | 160653 | 42277 | 25438 | 3043 | 1349 | 356 | 183 | 
| 2009 | 171442 | 47858 | 12211 | 7115 | 1157 | 452 | 180 | 
| 2010 | 233281 | 51586 | 13463 | 3530 | 2566 | 380 | 188 | 
| 2011 | 129832 | 70969 | 15198 | 3791 | 1381 | 922 | 190 | 
| 2012 | 191952 | 40579 | 23318 | 5578 | 1564 | 573 | 405 | 
| 2013 | 207524 | 59874 | 14109 | 8868 | 2650 | 663 | 412 | 
| 2014 | 299240 | 66769 | 21361 | 5599 | 4326 | 1290 | 521 |