| Year | Value | | 2022 | 2,443 | | 2021 | 2,405 | | 2020 | 2,398 | | 2019 | 2,442 | | 2018 | 2,522 | | 2017 | 2,633 | | 2016 | 2,750 | | 2015 | 2,843 | | 2014 | 2,898 | | 2013 | 2,917 | | 2012 | 2,907 | | 2011 | 2,882 | | 2010 | 2,860 | | 2009 | 2,818 | | 2008 | 2,769 | | 2007 | 2,764 | | 2006 | 2,809 | | 2005 | 2,901 | | 2004 | 3,006 | | 2003 | 3,101 | | 2002 | 3,187 | | 2001 | 3,271 | | 2000 | 3,346 | | 1999 | 3,403 | | 1998 | 3,519 | | 1997 | 3,711 | | 1996 | 3,885 | | 1995 | 3,973 | | 1994 | 3,914 | | 1993 | 3,722 | | 1992 | 3,523 | | 1991 | 3,392 | | 1990 | 3,294 | | 1989 | 3,127 | | 1988 | 3,038 | | 1987 | 2,955 | | 1986 | 2,890 | | 1985 | 2,895 | | 1984 | 3,002 | | 1983 | 3,161 | | 1982 | 3,349 | | 1981 | 3,581 | | 1980 | 3,799 | | 1979 | 3,806 | | 1978 | 3,899 | | 1977 | 3,861 | | 1976 | 4,018 | | 1975 | 3,993 | | 1974 | 3,834 | | 1973 | 3,573 | | 1972 | 3,214 | | 1971 | 2,961 | | 1970 | 2,612 | | 1969 | 2,402 | | 1968 | 2,142 | | 1967 | 1,865 | | 1966 | 1,772 | | 1965 | 1,715 | | 1964 | 1,630 | | 1963 | 1,563 | | 1962 | 1,337 | | 1961 | 1,264 | | 1960 | 1,043 |
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