| Year | Value | | 2022 | 26,020,453 | | 2021 | 25,553,105 | | 2020 | 25,213,109 | | 2019 | 24,842,841 | | 2018 | 24,340,329 | | 2017 | 23,795,760 | | 2016 | 23,195,946 | | 2015 | 22,540,832 | | 2014 | 21,865,689 | | 2013 | 21,222,684 | | 2012 | 20,650,946 | | 2011 | 20,130,396 | | 2010 | 19,636,696 | | 2009 | 19,104,263 | | 2008 | 18,491,119 | | 2007 | 17,841,558 | | 2006 | 17,207,139 | | 2005 | 16,658,346 | | 2004 | 16,217,959 | | 2003 | 15,839,373 | | 2002 | 15,475,330 | | 2001 | 15,118,023 | | 2000 | 14,761,838 | | 1999 | 14,400,445 | | 1998 | 14,044,268 | | 1997 | 13,705,030 | | 1996 | 13,377,765 | | 1995 | 13,066,150 | | 1994 | 12,774,312 | | 1993 | 12,483,512 | | 1992 | 12,215,060 | | 1991 | 11,930,768 | | 1990 | 11,554,307 | | 1989 | 11,166,798 | | 1988 | 10,792,988 | | 1987 | 10,440,442 | | 1986 | 10,100,168 | | 1985 | 9,778,305 | | 1984 | 9,473,259 | | 1983 | 9,185,973 | | 1982 | 8,911,216 | | 1981 | 8,630,427 | | 1980 | 8,362,426 | | 1979 | 8,086,196 | | 1978 | 7,820,168 | | 1977 | 7,557,715 | | 1976 | 7,300,318 | | 1975 | 7,045,924 | | 1974 | 6,802,646 | | 1973 | 6,571,435 | | 1972 | 6,352,148 | | 1971 | 6,136,152 | | 1970 | 5,928,099 | | 1969 | 5,730,190 | | 1968 | 5,539,180 | | 1967 | 5,354,457 | | 1966 | 5,177,832 | | 1965 | 4,999,206 | | 1964 | 4,823,084 | | 1963 | 4,650,867 | | 1962 | 4,486,045 | | 1961 | 4,328,206 | | 1960 | 4,183,473 |
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