| Year | Value | | 2022 | 21,187,537 | | 2021 | 21,296,190 | | 2020 | 21,483,909 | | 2019 | 21,562,915 | | 2018 | 21,417,797 | | 2017 | 21,179,227 | | 2016 | 20,880,065 | | 2015 | 20,551,060 | | 2014 | 20,240,464 | | 2013 | 19,872,066 | | 2012 | 19,397,819 | | 2011 | 18,885,838 | | 2010 | 18,295,599 | | 2009 | 17,538,386 | | 2008 | 16,704,335 | | 2007 | 15,891,047 | | 2006 | 15,126,925 | | 2005 | 14,483,996 | | 2004 | 13,971,672 | | 2003 | 13,515,410 | | 2002 | 13,102,070 | | 2001 | 12,707,453 | | 2000 | 12,295,146 | | 1999 | 11,896,078 | | 1998 | 11,509,960 | | 1997 | 11,144,829 | | 1996 | 10,802,859 | | 1995 | 10,464,053 | | 1994 | 10,124,616 | | 1993 | 9,833,444 | | 1992 | 9,544,193 | | 1991 | 9,206,105 | | 1990 | 8,867,197 | | 1989 | 8,497,690 | | 1988 | 8,203,153 | | 1987 | 7,917,318 | | 1986 | 7,614,277 | | 1985 | 7,297,221 | | 1984 | 6,990,316 | | 1983 | 6,681,058 | | 1982 | 6,367,866 | | 1981 | 6,012,952 | | 1980 | 5,654,868 | | 1979 | 5,336,112 | | 1978 | 5,041,008 | | 1977 | 4,781,083 | | 1976 | 4,543,603 | | 1975 | 4,355,905 | | 1974 | 4,220,327 | | 1973 | 4,127,516 | | 1972 | 4,071,436 | | 1971 | 4,040,106 | | 1970 | 4,014,134 | | 1969 | 3,986,596 | | 1968 | 3,956,283 | | 1967 | 3,918,977 | | 1966 | 3,872,944 | | 1965 | 3,819,541 | | 1964 | 3,754,034 | | 1963 | 3,677,337 | | 1962 | 3,595,675 | | 1961 | 3,514,243 | | 1960 | 3,442,307 |
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