| Year | Value | | 2022 | 310,812 | | 2021 | 315,903 | | 2020 | 334,773 | | 2019 | 348,605 | | 2018 | 359,879 | | 2017 | 367,675 | | 2016 | 373,652 | | 2015 | 378,034 | | 2014 | 380,281 | | 2013 | 382,696 | | 2012 | 387,137 | | 2011 | 390,678 | | 2010 | 386,432 | | 2009 | 377,759 | | 2008 | 368,131 | | 2007 | 350,088 | | 2006 | 327,417 | | 2005 | 311,555 | | 2004 | 298,712 | | 2003 | 282,119 | | 2002 | 267,511 | | 2001 | 257,073 | | 2000 | 249,121 | | 1999 | 244,780 | | 1998 | 245,118 | | 1997 | 249,747 | | 1996 | 257,638 | | 1995 | 267,367 | | 1994 | 276,169 | | 1993 | 283,043 | | 1992 | 288,303 | | 1991 | 292,120 | | 1990 | 296,064 | | 1989 | 301,034 | | 1988 | 307,359 | | 1987 | 314,205 | | 1986 | 319,551 | | 1985 | 321,176 | | 1984 | 312,620 | | 1983 | 287,089 | | 1982 | 251,280 | | 1981 | 217,037 | | 1980 | 193,506 | | 1979 | 192,377 | | 1978 | 215,771 | | 1977 | 250,193 | | 1976 | 283,803 | | 1975 | 309,862 | | 1974 | 322,771 | | 1973 | 326,139 | | 1972 | 326,507 | | 1971 | 326,071 | | 1970 | 324,891 | | 1969 | 321,652 | | 1968 | 317,206 | | 1967 | 313,839 | | 1966 | 310,323 | | 1965 | 307,585 | | 1964 | 304,900 | | 1963 | 299,552 | | 1962 | 292,692 | | 1961 | 285,075 | | 1960 | 278,959 |
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