| Year | Value | | 2022 | 18,317,452 | | 2021 | 17,809,262 | | 2020 | 17,296,009 | | 2019 | 16,773,700 | | 2018 | 16,254,743 | | 2017 | 15,749,558 | | 2016 | 15,260,019 | | 2015 | 14,781,636 | | 2014 | 14,314,480 | | 2013 | 13,861,896 | | 2012 | 13,421,112 | | 2011 | 12,996,243 | | 2010 | 12,593,200 | | 2009 | 12,215,127 | | 2008 | 11,862,272 | | 2007 | 11,528,899 | | 2006 | 11,209,989 | | 2005 | 10,896,268 | | 2004 | 10,559,979 | | 2003 | 10,218,134 | | 2002 | 9,911,921 | | 2001 | 9,634,226 | | 2000 | 9,372,082 | | 1999 | 9,140,494 | | 1998 | 8,922,218 | | 1997 | 8,683,842 | | 1996 | 8,436,118 | | 1995 | 8,194,524 | | 1994 | 7,976,648 | | 1993 | 7,786,495 | | 1992 | 7,612,021 | | 1991 | 7,447,945 | | 1990 | 7,282,996 | | 1989 | 7,113,088 | | 1988 | 6,950,212 | | 1987 | 6,793,716 | | 1986 | 6,639,735 | | 1985 | 6,495,092 | | 1984 | 6,356,949 | | 1983 | 6,217,454 | | 1982 | 6,073,289 | | 1981 | 5,927,163 | | 1980 | 5,793,443 | | 1979 | 5,666,045 | | 1978 | 5,530,642 | | 1977 | 5,401,685 | | 1976 | 5,280,606 | | 1975 | 5,159,412 | | 1974 | 5,040,701 | | 1973 | 4,921,617 | | 1972 | 4,802,675 | | 1971 | 4,685,894 | | 1970 | 4,568,898 | | 1969 | 4,454,797 | | 1968 | 4,347,122 | | 1967 | 4,244,725 | | 1966 | 4,146,270 | | 1965 | 4,051,286 | | 1964 | 3,959,443 | | 1963 | 3,871,841 | | 1962 | 3,788,000 | | 1961 | 3,706,412 | | 1960 | 3,628,573 |
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