| Year | Value | | 2022 | 2,979 | | 2021 | 2,909 | | 2020 | 2,838 | | 2019 | 2,795 | | 2018 | 2,811 | | 2017 | 2,843 | | 2016 | 2,901 | | 2015 | 2,999 | | 2014 | 3,141 | | 2013 | 3,313 | | 2012 | 3,492 | | 2011 | 3,654 | | 2010 | 3,783 | | 2009 | 3,829 | | 2008 | 3,806 | | 2007 | 3,780 | | 2006 | 3,773 | | 2005 | 3,792 | | 2004 | 3,855 | | 2003 | 3,950 | | 2002 | 4,039 | | 2001 | 4,103 | | 2000 | 4,160 | | 1999 | 4,142 | | 1998 | 4,016 | | 1997 | 3,874 | | 1996 | 3,759 | | 1995 | 3,592 | | 1994 | 3,429 | | 1993 | 3,408 | | 1992 | 3,463 | | 1991 | 3,591 | | 1990 | 3,808 | | 1989 | 3,997 | | 1988 | 4,332 | | 1987 | 4,702 | | 1986 | 5,066 | | 1985 | 5,377 | | 1984 | 5,626 | | 1983 | 5,805 | | 1982 | 5,842 | | 1981 | 5,669 | | 1980 | 5,298 | | 1979 | 4,678 | | 1978 | 4,293 | | 1977 | 3,962 | | 1976 | 4,018 | | 1975 | 3,928 | | 1974 | 3,679 | | 1973 | 3,368 | | 1972 | 3,041 | | 1971 | 2,873 | | 1970 | 2,628 | | 1969 | 2,539 | | 1968 | 2,383 | | 1967 | 2,115 | | 1966 | 1,961 | | 1965 | 1,768 | | 1964 | 1,599 | | 1963 | 1,545 | | 1962 | 1,340 | | 1961 | 1,284 | | 1960 | 1,374 |
|