| Year | Value | | 2022 | 1,434 | | 2021 | 1,398 | | 2020 | 1,365 | | 2019 | 1,342 | | 2018 | 1,344 | | 2017 | 1,342 | | 2016 | 1,329 | | 2015 | 1,317 | | 2014 | 1,292 | | 2013 | 1,258 | | 2012 | 1,248 | | 2011 | 1,264 | | 2010 | 1,285 | | 2009 | 1,283 | | 2008 | 1,254 | | 2007 | 1,220 | | 2006 | 1,201 | | 2005 | 1,204 | | 2004 | 1,225 | | 2003 | 1,266 | | 2002 | 1,303 | | 2001 | 1,316 | | 2000 | 1,309 | | 1999 | 1,292 | | 1998 | 1,270 | | 1997 | 1,256 | | 1996 | 1,256 | | 1995 | 1,262 | | 1994 | 1,264 | | 1993 | 1,261 | | 1992 | 1,250 | | 1991 | 1,223 | | 1990 | 1,184 | | 1989 | 1,142 | | 1988 | 1,100 | | 1987 | 1,074 | | 1986 | 1,081 | | 1985 | 1,100 | | 1984 | 1,110 | | 1983 | 1,101 | | 1982 | 1,072 | | 1981 | 1,030 | | 1980 | 986 | | 1979 | 944 | | 1978 | 907 | | 1977 | 873 | | 1976 | 845 | | 1975 | 823 | | 1974 | 797 | | 1973 | 772 | | 1972 | 749 | | 1971 | 728 | | 1970 | 711 | | 1969 | 698 | | 1968 | 685 | | 1967 | 672 | | 1966 | 657 | | 1965 | 644 | | 1964 | 631 | | 1963 | 618 | | 1962 | 603 | | 1961 | 587 | | 1960 | 568 |
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