| Year | Value | | 2022 | 19,261,533 | | 2021 | 19,200,114 | | 2020 | 19,316,685 | | 2019 | 19,354,582 | | 2018 | 19,236,892 | | 2017 | 19,135,666 | | 2016 | 18,998,314 | | 2015 | 18,843,571 | | 2014 | 18,775,952 | | 2013 | 18,736,536 | | 2012 | 18,630,980 | | 2011 | 18,472,905 | | 2010 | 18,241,122 | | 2009 | 17,761,193 | | 2008 | 17,043,780 | | 2007 | 16,249,787 | | 2006 | 15,482,516 | | 2005 | 14,857,156 | | 2004 | 14,383,749 | | 2003 | 13,940,202 | | 2002 | 13,451,858 | | 2001 | 12,960,585 | | 2000 | 12,490,904 | | 1999 | 12,059,857 | | 1998 | 11,675,843 | | 1997 | 11,319,622 | | 1996 | 10,984,959 | | 1995 | 10,657,811 | | 1994 | 10,306,455 | | 1993 | 9,935,273 | | 1992 | 9,605,801 | | 1991 | 9,312,692 | | 1990 | 9,044,418 | | 1989 | 8,712,164 | | 1988 | 8,434,913 | | 1987 | 8,160,709 | | 1986 | 7,891,324 | | 1985 | 7,633,386 | | 1984 | 7,378,622 | | 1983 | 7,133,392 | | 1982 | 6,888,669 | | 1981 | 6,631,135 | | 1980 | 6,347,117 | | 1979 | 6,042,472 | | 1978 | 5,759,950 | | 1977 | 5,505,865 | | 1976 | 5,256,229 | | 1975 | 5,018,547 | | 1974 | 4,784,341 | | 1973 | 4,550,723 | | 1972 | 4,333,190 | | 1971 | 4,141,400 | | 1970 | 3,984,810 | | 1969 | 3,865,192 | | 1968 | 3,780,074 | | 1967 | 3,724,957 | | 1966 | 3,690,066 | | 1965 | 3,659,106 | | 1964 | 3,626,064 | | 1963 | 3,592,617 | | 1962 | 3,555,750 | | 1961 | 3,514,069 | | 1960 | 3,471,241 |
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