| Year | Value | | 2022 | 16,258,865 | | 2021 | 15,829,017 | | 2020 | 15,383,776 | | 2019 | 14,948,292 | | 2018 | 14,498,345 | | 2017 | 14,050,726 | | 2016 | 13,603,868 | | 2015 | 13,097,030 | | 2014 | 12,571,538 | | 2013 | 12,067,579 | | 2012 | 11,563,973 | | 2011 | 11,084,523 | | 2010 | 10,622,405 | | 2009 | 10,194,878 | | 2008 | 9,824,739 | | 2007 | 9,480,814 | | 2006 | 9,131,066 | | 2005 | 8,782,564 | | 2004 | 8,438,944 | | 2003 | 8,092,897 | | 2002 | 7,760,610 | | 2001 | 7,473,099 | | 2000 | 7,229,336 | | 1999 | 7,001,266 | | 1998 | 6,787,992 | | 1997 | 6,588,945 | | 1996 | 6,377,031 | | 1995 | 6,139,562 | | 1994 | 5,903,951 | | 1993 | 5,675,782 | | 1992 | 5,437,888 | | 1991 | 5,188,895 | | 1990 | 4,970,832 | | 1989 | 4,719,142 | | 1988 | 4,470,778 | | 1987 | 4,232,082 | | 1986 | 4,009,167 | | 1985 | 3,822,877 | | 1984 | 3,679,876 | | 1983 | 3,571,547 | | 1982 | 3,492,027 | | 1981 | 3,435,835 | | 1980 | 3,384,007 | | 1979 | 3,325,457 | | 1978 | 3,274,633 | | 1977 | 3,227,430 | | 1976 | 3,166,298 | | 1975 | 3,102,984 | | 1974 | 3,041,783 | | 1973 | 2,974,382 | | 1972 | 2,904,643 | | 1971 | 2,835,458 | | 1970 | 2,767,991 | | 1969 | 2,699,630 | | 1968 | 2,629,031 | | 1967 | 2,558,294 | | 1966 | 2,489,102 | | 1965 | 2,420,533 | | 1964 | 2,352,925 | | 1963 | 2,287,111 | | 1962 | 2,224,183 | | 1961 | 2,165,927 | | 1960 | 2,111,755 |
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