| Year | Value | | 2022 | 2,792 | | 2021 | 2,835 | | 2020 | 2,862 | | 2019 | 2,860 | | 2018 | 2,828 | | 2017 | 2,769 | | 2016 | 2,691 | | 2015 | 2,599 | | 2014 | 2,499 | | 2013 | 2,396 | | 2012 | 2,286 | | 2011 | 2,176 | | 2010 | 2,076 | | 2009 | 1,987 | | 2008 | 1,906 | | 2007 | 1,842 | | 2006 | 1,794 | | 2005 | 1,744 | | 2004 | 1,688 | | 2003 | 1,629 | | 2002 | 1,564 | | 2001 | 1,498 | | 2000 | 1,433 | | 1999 | 1,371 | | 1998 | 1,324 | | 1997 | 1,297 | | 1996 | 1,284 | | 1995 | 1,287 | | 1994 | 1,296 | | 1993 | 1,295 | | 1992 | 1,280 | | 1991 | 1,246 | | 1990 | 1,200 | | 1989 | 1,152 | | 1988 | 1,107 | | 1987 | 1,071 | | 1986 | 1,048 | | 1985 | 1,038 | | 1984 | 1,036 | | 1983 | 1,039 | | 1982 | 1,042 | | 1981 | 1,041 | | 1980 | 1,038 | | 1979 | 1,030 | | 1978 | 1,018 | | 1977 | 1,008 | | 1976 | 1,004 | | 1975 | 1,013 | | 1974 | 1,032 | | 1973 | 1,034 | | 1972 | 1,017 | | 1971 | 1,000 | | 1970 | 987 | | 1969 | 981 | | 1968 | 969 | | 1967 | 949 | | 1966 | 937 | | 1965 | 930 | | 1964 | 922 | | 1963 | 911 | | 1962 | 897 | | 1961 | 882 | | 1960 | 867 |
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