| Year | Value | | 2023 | 17,307,639 | | 2022 | 17,129,366 | | 2021 | 16,996,006 | | 2020 | 16,627,612 | | 2019 | 16,435,873 | | 2018 | 16,042,818 | | 2017 | 15,658,484 | | 2016 | 15,327,169 | | 2015 | 15,045,055 | | 2014 | 14,684,559 | | 2013 | 14,299,077 | | 2012 | 13,645,753 | | 2011 | 13,097,899 | | 2010 | 12,521,773 | | 2009 | 12,181,257 | | 2008 | 11,759,285 | | 2007 | 11,495,326 | | 2006 | 11,150,446 | | 2005 | 10,820,229 | | 2004 | 10,502,969 | | 2003 | 10,199,219 | | 2002 | 9,907,167 | | 2001 | 9,625,678 | | 2000 | 9,350,453 | | 1999 | 9,077,511 | | 1998 | 8,795,586 | | 1997 | 8,507,658 | | 1996 | 8,243,318 | | 1995 | 7,993,191 | | 1994 | 7,750,796 | | 1993 | 7,516,894 | | 1992 | 7,293,606 | | 1991 | 7,073,003 |
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