| Year | Value | | 2022 | 5,614 | | 2021 | 5,607 | | 2020 | 5,572 | | 2019 | 5,537 | | 2018 | 5,495 | | 2017 | 5,420 | | 2016 | 5,293 | | 2015 | 5,127 | | 2014 | 4,957 | | 2013 | 4,803 | | 2012 | 4,691 | | 2011 | 4,663 | | 2010 | 4,708 | | 2009 | 4,772 | | 2008 | 4,823 | | 2007 | 4,841 | | 2006 | 4,797 | | 2005 | 4,704 | | 2004 | 4,596 | | 2003 | 4,480 | | 2002 | 4,366 | | 2001 | 4,241 | | 2000 | 4,102 | | 1999 | 3,962 | | 1998 | 3,828 | | 1997 | 3,697 | | 1996 | 3,569 | | 1995 | 3,443 | | 1994 | 3,323 | | 1993 | 3,214 | | 1992 | 3,119 | | 1991 | 3,051 | | 1990 | 3,010 | | 1989 | 2,994 | | 1988 | 3,014 | | 1987 | 3,056 | | 1986 | 3,075 | | 1985 | 3,071 | | 1984 | 3,071 | | 1983 | 3,082 | | 1982 | 3,098 | | 1981 | 3,105 | | 1980 | 3,092 | | 1979 | 3,063 | | 1978 | 3,031 | | 1977 | 3,001 | | 1976 | 2,955 | | 1975 | 2,911 | | 1974 | 2,909 | | 1973 | 2,923 | | 1972 | 2,916 | | 1971 | 2,866 | | 1970 | 2,773 | | 1969 | 2,648 | | 1968 | 2,510 | | 1967 | 2,376 | | 1966 | 2,268 | | 1965 | 2,189 | | 1964 | 2,124 | | 1963 | 2,074 | | 1962 | 2,029 | | 1961 | 1,980 | | 1960 | 1,931 |
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