| Year | Value | | 2022 | 38,594 | | 2021 | 38,538 | | 2020 | 38,644 | | 2019 | 38,467 | | 2018 | 38,342 | | 2017 | 38,415 | | 2016 | 38,880 | | 2015 | 39,818 | | 2014 | 41,076 | | 2013 | 42,666 | | 2012 | 44,641 | | 2011 | 43,231 | | 2010 | 38,526 | | 2009 | 34,303 | | 2008 | 30,641 | | 2007 | 27,696 | | 2006 | 25,578 | | 2005 | 24,134 | | 2004 | 23,128 | | 2003 | 22,542 | | 2002 | 20,779 | | 2001 | 17,010 | | 2000 | 13,073 | | 1999 | 10,031 | | 1998 | 7,892 | | 1997 | 7,054 | | 1996 | 6,478 | | 1995 | 5,760 | | 1994 | 7,967 | | 1993 | 10,324 | | 1992 | 10,362 | | 1991 | 10,393 | | 1990 | 10,409 | | 1989 | 10,411 | | 1988 | 10,330 | | 1987 | 10,115 | | 1986 | 9,833 | | 1985 | 9,572 | | 1984 | 9,396 | | 1983 | 9,303 | | 1982 | 9,181 | | 1981 | 8,990 | | 1980 | 8,777 | | 1979 | 8,562 | | 1978 | 8,364 | | 1977 | 8,182 | | 1976 | 8,010 | | 1975 | 7,864 | | 1974 | 7,749 | | 1973 | 7,656 | | 1972 | 7,552 | | 1971 | 7,392 | | 1970 | 7,158 | | 1969 | 6,844 | | 1968 | 6,437 | | 1967 | 5,951 | | 1966 | 5,463 | | 1965 | 5,042 | | 1964 | 4,695 | | 1963 | 4,434 | | 1962 | 4,249 | | 1961 | 4,084 | | 1960 | 3,914 |
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