| Year | Value | | 2022 | 4,927 | | 2021 | 4,774 | | 2020 | 4,700 | | 2019 | 4,702 | | 2018 | 4,742 | | 2017 | 4,724 | | 2016 | 4,628 | | 2015 | 4,548 | | 2014 | 4,517 | | 2013 | 4,504 | | 2012 | 4,571 | | 2011 | 4,663 | | 2010 | 4,636 | | 2009 | 4,509 | | 2008 | 4,335 | | 2007 | 4,060 | | 2006 | 3,733 | | 2005 | 3,535 | | 2004 | 3,492 | | 2003 | 3,499 | | 2002 | 3,533 | | 2001 | 3,583 | | 2000 | 3,612 | | 1999 | 3,579 | | 1998 | 3,507 | | 1997 | 3,430 | | 1996 | 3,346 | | 1995 | 3,270 | | 1994 | 3,214 | | 1993 | 3,155 | | 1992 | 3,120 | | 1991 | 3,140 | | 1990 | 3,161 | | 1989 | 3,163 | | 1988 | 3,170 | | 1987 | 3,194 | | 1986 | 3,205 | | 1985 | 3,175 | | 1984 | 3,113 | | 1983 | 3,032 | | 1982 | 2,943 | | 1981 | 2,864 | | 1980 | 2,805 | | 1979 | 2,813 | | 1978 | 2,933 | | 1977 | 3,117 | | 1976 | 3,297 | | 1975 | 3,403 | | 1974 | 3,434 | | 1973 | 3,438 | | 1972 | 3,423 | | 1971 | 3,394 | | 1970 | 3,358 | | 1969 | 3,306 | | 1968 | 3,244 | | 1967 | 3,171 | | 1966 | 3,093 | | 1965 | 3,023 | | 1964 | 2,961 | | 1963 | 2,893 | | 1962 | 2,820 | | 1961 | 2,757 | | 1960 | 2,684 |
|