| Year | Value | | 2022 | 21,721,706 | | 2021 | 20,973,836 | | 2020 | 20,283,206 | | 2019 | 19,622,699 | | 2018 | 18,990,009 | | 2017 | 18,371,604 | | 2016 | 17,769,255 | | 2015 | 17,171,358 | | 2014 | 16,576,524 | | 2013 | 16,004,687 | | 2012 | 15,456,033 | | 2011 | 14,926,405 | | 2010 | 14,411,419 | | 2009 | 13,910,508 | | 2008 | 13,429,926 | | 2007 | 12,972,984 | | 2006 | 12,547,725 | | 2005 | 12,163,443 | | 2004 | 11,815,904 | | 2003 | 11,500,767 | | 2002 | 11,212,662 | | 2001 | 10,938,414 | | 2000 | 10,665,386 | | 1999 | 10,379,283 | | 1998 | 10,092,297 | | 1997 | 9,844,561 | | 1996 | 9,639,103 | | 1995 | 9,448,622 | | 1994 | 9,277,560 | | 1993 | 9,114,312 | | 1992 | 8,914,751 | | 1991 | 8,678,828 | | 1990 | 8,434,035 | | 1989 | 8,194,844 | | 1988 | 7,981,679 | | 1987 | 7,787,772 | | 1986 | 7,596,050 | | 1985 | 7,432,121 | | 1984 | 7,291,362 | | 1983 | 7,150,563 | | 1982 | 7,004,163 | | 1981 | 6,853,665 | | 1980 | 6,724,141 | | 1979 | 6,596,429 | | 1978 | 6,445,135 | | 1977 | 6,300,413 | | 1976 | 6,168,476 | | 1975 | 6,034,562 | | 1974 | 5,899,474 | | 1973 | 5,765,931 | | 1972 | 5,636,484 | | 1971 | 5,511,113 | | 1970 | 5,388,829 | | 1969 | 5,275,305 | | 1968 | 5,167,522 | | 1967 | 5,061,462 | | 1966 | 4,956,834 | | 1965 | 4,850,688 | | 1964 | 4,743,479 | | 1963 | 4,639,376 | | 1962 | 4,538,739 | | 1961 | 4,440,097 | | 1960 | 4,348,461 |
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