| Year | Value | | 2022 | 3,808 | | 2021 | 3,558 | | 2020 | 3,373 | | 2019 | 3,262 | | 2018 | 3,208 | | 2017 | 3,183 | | 2016 | 3,173 | | 2015 | 3,164 | | 2014 | 3,153 | | 2013 | 3,152 | | 2012 | 3,166 | | 2011 | 3,196 | | 2010 | 3,254 | | 2009 | 3,326 | | 2008 | 3,397 | | 2007 | 3,459 | | 2006 | 3,506 | | 2005 | 3,528 | | 2004 | 3,519 | | 2003 | 3,478 | | 2002 | 3,406 | | 2001 | 3,299 | | 2000 | 3,177 | | 1999 | 3,057 | | 1998 | 2,928 | | 1997 | 2,793 | | 1996 | 2,661 | | 1995 | 2,533 | | 1994 | 2,407 | | 1993 | 2,275 | | 1992 | 2,144 | | 1991 | 2,030 | | 1990 | 1,946 | | 1989 | 1,893 | | 1988 | 1,854 | | 1987 | 1,823 | | 1986 | 1,797 | | 1985 | 1,766 | | 1984 | 1,735 | | 1983 | 1,712 | | 1982 | 1,699 | | 1981 | 1,697 | | 1980 | 1,713 | | 1979 | 1,748 | | 1978 | 1,793 | | 1977 | 1,842 | | 1976 | 1,898 | | 1975 | 1,957 | | 1974 | 2,003 | | 1973 | 2,036 | | 1972 | 2,060 | | 1971 | 2,070 | | 1970 | 2,072 | | 1969 | 2,077 | | 1968 | 2,084 | | 1967 | 2,085 | | 1966 | 2,083 | | 1965 | 2,078 | | 1964 | 2,075 | | 1963 | 2,068 | | 1962 | 2,061 | | 1961 | 2,055 | | 1960 | 2,049 |
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