| Year | Value | | 2024 | 16,634,373 | | 2023 | 16,340,822 | | 2022 | 16,069,056 | | 2021 | 15,797,210 | | 2020 | 15,526,888 | | 2019 | 15,271,368 | | 2018 | 15,034,452 | | 2017 | 14,812,482 | | 2016 | 14,600,294 | | 2015 | 14,399,013 | | 2014 | 14,207,359 | | 2013 | 14,013,808 | | 2012 | 13,817,887 | | 2011 | 13,595,424 | | 2010 | 13,356,548 | | 2009 | 13,142,790 | | 2008 | 12,959,149 | | 2007 | 12,804,058 | | 2006 | 12,636,445 | | 2005 | 12,483,432 | | 2004 | 12,365,896 | | 2003 | 12,232,323 | | 2002 | 12,087,653 | | 2001 | 11,971,901 | | 2000 | 11,892,055 | | 1999 | 11,783,458 | | 1998 | 11,594,297 | | 1997 | 11,369,827 | | 1996 | 11,158,360 | | 1995 | 10,974,599 | | 1994 | 10,873,148 | | 1993 | 10,860,288 | | 1992 | 10,702,700 | | 1991 | 10,404,816 | | 1990 | 10,137,281 | | 1989 | 9,864,798 | | 1988 | 9,583,094 | | 1987 | 9,284,644 | | 1986 | 8,982,578 | | 1985 | 8,686,813 | | 1984 | 8,391,488 | | 1983 | 8,098,404 | | 1982 | 7,796,496 | | 1981 | 7,498,635 | | 1980 | 7,041,303 | | 1979 | 6,647,556 | | 1978 | 6,543,575 | | 1977 | 6,449,512 | | 1976 | 6,287,105 | | 1975 | 6,098,658 |
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