| Year | Value | | 2022 | 317,681 | | 2021 | 309,648 | | 2020 | 304,331 | | 2019 | 300,247 | | 2018 | 297,214 | | 2017 | 295,574 | | 2016 | 295,901 | | 2015 | 292,508 | | 2014 | 284,018 | | 2013 | 274,547 | | 2012 | 261,000 | | 2011 | 242,330 | | 2010 | 226,925 | | 2009 | 221,002 | | 2008 | 218,804 | | 2007 | 220,787 | | 2006 | 226,411 | | 2005 | 231,113 | | 2004 | 232,316 | | 2003 | 231,862 | | 2002 | 232,606 | | 2001 | 235,824 | | 2000 | 240,300 | | 1999 | 243,335 | | 1998 | 244,107 | | 1997 | 243,137 | | 1996 | 240,483 | | 1995 | 238,085 | | 1994 | 237,290 | | 1993 | 237,692 | | 1992 | 237,816 | | 1991 | 237,718 | | 1990 | 237,285 | | 1989 | 231,355 | | 1988 | 214,980 | | 1987 | 193,680 | | 1986 | 173,890 | | 1985 | 157,733 | | 1984 | 153,247 | | 1983 | 163,716 | | 1982 | 180,753 | | 1981 | 195,988 | | 1980 | 206,119 | | 1979 | 209,646 | | 1978 | 209,452 | | 1977 | 209,305 | | 1976 | 210,202 | | 1975 | 211,218 | | 1974 | 211,760 | | 1973 | 212,357 | | 1972 | 212,720 | | 1971 | 213,570 | | 1970 | 214,301 | | 1969 | 213,328 | | 1968 | 211,060 | | 1967 | 207,992 | | 1966 | 203,727 | | 1965 | 198,949 | | 1964 | 193,973 | | 1963 | 189,214 | | 1962 | 184,386 | | 1961 | 179,704 | | 1960 | 175,873 |
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