| Year | Value | | 2022 | 2,764 | | 2021 | 2,884 | | 2020 | 2,965 | | 2019 | 3,010 | | 2018 | 3,017 | | 2017 | 3,009 | | 2016 | 3,004 | | 2015 | 3,019 | | 2014 | 3,066 | | 2013 | 3,140 | | 2012 | 3,219 | | 2011 | 3,286 | | 2010 | 3,333 | | 2009 | 3,346 | | 2008 | 3,286 | | 2007 | 3,148 | | 2006 | 2,986 | | 2005 | 2,856 | | 2004 | 2,855 | | 2003 | 2,982 | | 2002 | 3,150 | | 2001 | 3,327 | | 2000 | 3,481 | | 1999 | 3,494 | | 1998 | 3,395 | | 1997 | 3,301 | | 1996 | 3,263 | | 1995 | 3,354 | | 1994 | 3,610 | | 1993 | 3,953 | | 1992 | 4,231 | | 1991 | 4,328 | | 1990 | 4,222 | | 1989 | 3,946 | | 1988 | 3,740 | | 1987 | 3,528 | | 1986 | 3,445 | | 1985 | 3,471 | | 1984 | 3,484 | | 1983 | 3,516 | | 1982 | 3,598 | | 1981 | 3,690 | | 1980 | 3,819 | | 1979 | 3,830 | | 1978 | 3,914 | | 1977 | 3,889 | | 1976 | 4,136 | | 1975 | 4,198 | | 1974 | 4,138 | | 1973 | 4,002 | | 1972 | 3,731 | | 1971 | 3,533 | | 1970 | 3,195 | | 1969 | 2,941 | | 1968 | 2,522 | | 1967 | 2,083 | | 1966 | 1,876 | | 1965 | 1,750 | | 1964 | 1,662 | | 1963 | 1,637 | | 1962 | 1,447 | | 1961 | 1,425 | | 1960 | 1,196 |
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