| Year | Value | | 2023 | 16,933,906 | | 2022 | 16,617,140 | | 2021 | 16,336,779 | | 2020 | 15,995,144 | | 2019 | 15,485,557 | | 2018 | 14,523,667 | | 2017 | 13,926,541 | | 2016 | 13,967,604 | | 2015 | 13,441,489 | | 2014 | 12,977,992 | | 2013 | 12,635,859 | | 2012 | 12,176,429 | | 2011 | 11,614,140 | | 2010 | 11,036,836 | | 2009 | 10,384,920 | | 2008 | 9,918,243 | | 2007 | 9,448,425 | | 2006 | 8,989,951 | | 2005 | 8,558,784 | | 2004 | 8,227,971 | | 2003 | 7,948,017 | | 2002 | 7,625,337 | | 2001 | 7,333,273 | | 2000 | 7,079,451 | | 1999 | 6,656,494 | | 1998 | 6,444,044 | | 1997 | 6,257,970 | | 1996 | 6,085,542 | | 1995 | 5,926,862 | | 1994 | 5,775,354 | | 1993 | 5,636,555 | | 1992 | 5,467,076 | | 1991 | 5,211,327 |
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