| Year | Value | | 2022 | 15,797 | | 2021 | 15,750 | | 2020 | 15,560 | | 2019 | 15,089 | | 2018 | 14,478 | | 2017 | 13,873 | | 2016 | 13,306 | | 2015 | 12,785 | | 2014 | 12,250 | | 2013 | 11,703 | | 2012 | 11,215 | | 2011 | 10,718 | | 2010 | 10,123 | | 2009 | 9,517 | | 2008 | 8,959 | | 2007 | 8,540 | | 2006 | 8,387 | | 2005 | 8,445 | | 2004 | 8,600 | | 2003 | 8,826 | | 2002 | 9,082 | | 2001 | 9,316 | | 2000 | 9,570 | | 1999 | 9,962 | | 1998 | 10,329 | | 1997 | 10,602 | | 1996 | 10,811 | | 1995 | 10,815 | | 1994 | 10,674 | | 1993 | 10,370 | | 1992 | 9,887 | | 1991 | 9,348 | | 1990 | 8,791 | | 1989 | 8,314 | | 1988 | 7,871 | | 1987 | 7,479 | | 1986 | 7,184 | | 1985 | 6,965 | | 1984 | 6,804 | | 1983 | 6,709 | | 1982 | 6,654 | | 1981 | 6,579 | | 1980 | 6,464 | | 1979 | 6,325 | | 1978 | 6,164 | | 1977 | 5,961 | | 1976 | 5,728 | | 1975 | 5,503 | | 1974 | 5,289 | | 1973 | 5,087 | | 1972 | 4,900 | | 1971 | 4,731 | | 1970 | 4,599 | | 1969 | 4,487 | | 1968 | 4,370 | | 1967 | 4,245 | | 1966 | 4,109 | | 1965 | 3,976 | | 1964 | 3,853 | | 1963 | 3,725 | | 1962 | 3,595 | | 1961 | 3,481 | | 1960 | 3,384 |
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