| Year | Value | | 2022 | 20,764,829 | | 2021 | 19,823,963 | | 2020 | 19,274,309 | | 2019 | 18,953,008 | | 2018 | 18,783,891 | | 2017 | 18,739,261 | | 2016 | 18,558,318 | | 2015 | 18,225,820 | | 2014 | 17,879,388 | | 2013 | 17,487,708 | | 2012 | 16,989,258 | | 2011 | 16,439,811 | | 2010 | 15,961,922 | | 2009 | 15,551,586 | | 2008 | 15,132,729 | | 2007 | 14,713,678 | | 2006 | 14,288,447 | | 2005 | 13,795,802 | | 2004 | 13,280,908 | | 2003 | 12,723,596 | | 2002 | 12,093,478 | | 2001 | 11,513,440 | | 2000 | 10,955,970 | | 1999 | 10,352,516 | | 1998 | 9,753,705 | | 1997 | 9,235,617 | | 1996 | 8,785,608 | | 1995 | 8,401,376 | | 1994 | 8,137,011 | | 1993 | 7,995,432 | | 1992 | 7,895,346 | | 1991 | 7,784,390 | | 1990 | 7,647,726 | | 1989 | 7,425,907 | | 1988 | 7,132,884 | | 1987 | 6,856,309 | | 1986 | 6,619,040 | | 1985 | 6,392,111 | | 1984 | 6,153,358 | | 1983 | 5,932,599 | | 1982 | 5,732,441 | | 1981 | 5,520,644 | | 1980 | 5,304,287 | | 1979 | 5,069,982 | | 1978 | 4,800,983 | | 1977 | 4,534,891 | | 1976 | 4,298,832 | | 1975 | 4,092,300 | | 1974 | 3,928,007 | | 1973 | 3,795,798 | | 1972 | 3,667,846 | | 1971 | 3,537,366 | | 1970 | 3,408,586 | | 1969 | 3,298,095 | | 1968 | 3,208,268 | | 1967 | 3,130,634 | | 1966 | 3,072,240 | | 1965 | 3,034,079 | | 1964 | 2,997,113 | | 1963 | 2,940,937 | | 1962 | 2,886,354 | | 1961 | 2,875,118 | | 1960 | 2,928,960 |
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