| Table 2. Estimated stock numbers. | |||||
| Year\Age | 0 | 1 | 2 | 3 | 4+ |
| 1970 | 16902972 | 17435170 | 17348212 | 13470329 | 42541899 |
| 1971 | 16651319 | 16970719 | 17435170 | 13714991 | 41243332 |
| 1972 | 16419825 | 16634676 | 17004694 | 13783737 | 40548121 |
| 1973 | 16207749 | 16419825 | 16634676 | 13443416 | 40104536 |
| 1974 | 15950488 | 16207749 | 16419825 | 13150890 | 39507457 |
| 1975 | 15697311 | 15950488 | 16207749 | 12981035 | 38841507 |
| 1976 | 15448153 | 15697311 | 15950488 | 12813374 | 38263232 |
| 1977 | 15202949 | 15448153 | 15681622 | 12609991 | 37655892 |
| 1978 | 14961638 | 15202949 | 15417287 | 12397433 | 37058192 |
| 1979 | 14694738 | 14916820 | 15142259 | 12151947 | 36324391 |
| 1980 | 14317598 | 14665377 | 14797962 | 11875642 | 35250843 |
| 1981 | 13537850 | 14389366 | 14548522 | 10831835 | 32834817 |
| 1982 | 12225078 | 13646587 | 14317598 | 10596136 | 28602366 |
| 1983 | 11184059 | 12151947 | 13578524 | 10417525 | 25674273 |
| 1984 | 10355207 | 11117155 | 12031034 | 9889657 | 23724053 |
| 1985 | 9568624 | 10334517 | 11006538 | 8745064 | 22142292 |
| 1986 | 8788899 | 9549506 | 10241923 | 8000383 | 20317639 |
| 1987 | 8088873 | 8762572 | 9473415 | 7452052 | 18624715 |
| 1988 | 7452052 | 8064643 | 8684062 | 6892883 | 17158427 |
| 1989 | 6885994 | 7422303 | 8000383 | 6331198 | 15855072 |
| 1990 | 6388436 | 6885994 | 7355802 | 5867857 | 14694738 |
| 1991 | 6010389 | 6382051 | 6879111 | 5378930 | 14006051 |
| 1992 | 6064726 | 5926830 | 6420458 | 5885487 | 14592234 |
| 1993 | 6635868 | 5968463 | 5944637 | 5515098 | 17175594 |
| 1994 | 7102803 | 6695860 | 5986395 | 5101270 | 18981967 |
| 1995 | 7459508 | 7167016 | 6783475 | 5137104 | 19995144 |
| 1996 | 7841965 | 7481920 | 7253539 | 5838591 | 20769581 |
| 1997 | 8310248 | 7857665 | 7557115 | 6243179 | 22031857 |
| 1998 | 8797692 | 8326885 | 7928703 | 6497968 | 23417637 |
| 1999 | 9285829 | 8824125 | 8393767 | 6810663 | 24692250 |
| 2000 | 9791253 | 9304419 | 8877229 | 7174187 | 25828782 |
| 2001 | 10252171 | 9810855 | 9351058 | 7663658 | 26695351 |
| 2002 | 10427947 | 10334517 | 9820671 | 7437163 | 27071715 |
| 2003 | 10089441 | 10553836 | 10365567 | 7779480 | 25393404 |
| 2004 | 9860032 | 10059218 | 10606738 | 8202914 | 24324631 |
| 2005 | 9752166 | 9820671 | 10049164 | 8393767 | 23986459 |
| 2006 | 9635840 | 9752166 | 9810855 | 7944576 | 23914607 |
| 2007 | 9482893 | 9645480 | 9752166 | 7756176 | 23511495 |
| 2008 | 9323046 | 9482893 | 9655131 | 7709778 | 23068993 |
| 2009 | 9184244 | 9313728 | 9473415 | 7633065 | 22702827 |
| 2010 | 9047509 | 9184244 | 9313728 | 7496899 | 22387202 |
| 2011 | 8912809 | 9047509 | 9184244 | 7363162 | 22053900 |
| 2012 | 8771339 | 8912809 | 9047509 | 7260796 | 21703845 |
| 2013 | 8649396 | 8771339 | 8912809 | 7152697 | 21380717 |
| 2014 | 8520623 | 8649396 | 8771339 | 7046207 | 21041348 |
| 2015 | 8435841 | 8512106 | 8666712 | 6927434 | 20686668 |