| Year | Value | | 2022 | 20,710,108 | | 2021 | 20,080,173 | | 2020 | 19,436,715 | | 2019 | 18,868,020 | | 2018 | 18,318,948 | | 2017 | 17,720,256 | | 2016 | 17,079,794 | | 2015 | 16,382,097 | | 2014 | 15,659,920 | | 2013 | 14,929,325 | | 2012 | 14,237,730 | | 2011 | 13,639,411 | | 2010 | 13,061,644 | | 2009 | 12,482,462 | | 2008 | 11,909,826 | | 2007 | 11,346,054 | | 2006 | 10,844,952 | | 2005 | 10,327,146 | | 2004 | 9,750,406 | | 2003 | 9,205,920 | | 2002 | 8,727,796 | | 2001 | 8,272,695 | | 2000 | 7,848,479 | | 1999 | 7,490,549 | | 1998 | 7,169,747 | | 1997 | 6,857,258 | | 1996 | 6,553,488 | | 1995 | 6,251,611 | | 1994 | 5,949,058 | | 1993 | 5,659,018 | | 1992 | 5,429,396 | | 1991 | 5,270,055 | | 1990 | 5,113,986 | | 1989 | 4,909,188 | | 1988 | 4,677,000 | | 1987 | 4,461,179 | | 1986 | 4,248,472 | | 1985 | 4,016,111 | | 1984 | 3,777,163 | | 1983 | 3,531,431 | | 1982 | 3,291,047 | | 1981 | 3,069,927 | | 1980 | 2,869,651 | | 1979 | 2,704,143 | | 1978 | 2,557,289 | | 1977 | 2,413,530 | | 1976 | 2,282,015 | | 1975 | 2,152,388 | | 1974 | 2,022,695 | | 1973 | 1,898,821 | | 1972 | 1,790,796 | | 1971 | 1,714,420 | | 1970 | 1,661,000 | | 1969 | 1,610,918 | | 1968 | 1,555,709 | | 1967 | 1,504,953 | | 1966 | 1,468,957 | | 1965 | 1,446,830 | | 1964 | 1,443,397 | | 1963 | 1,444,224 | | 1962 | 1,430,974 | | 1961 | 1,437,113 | | 1960 | 1,492,629 |
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