| Year | Value | | 2023 | 18,772,903 | | 2022 | 18,241,181 | | 2021 | 17,906,140 | | 2020 | 16,817,064 | | 2019 | 16,249,934 | | 2018 | 14,719,292 | | 2017 | 14,880,554 | | 2016 | 15,057,018 | | 2015 | 15,246,203 | | 2014 | 14,333,376 | | 2013 | 13,976,230 | | 2012 | 13,559,113 | | 2011 | 13,103,614 | | 2010 | 12,653,854 | | 2009 | 11,703,308 | | 2008 | 10,753,977 | | 2007 | 10,163,749 | | 2006 | 9,688,698 | | 2005 | 9,123,483 | | 2004 | 8,592,240 | | 2003 | 7,981,093 | | 2002 | 7,419,709 | | 2001 | 7,170,098 | | 2000 | 6,866,123 | | 1999 | 6,414,316 | | 1998 | 6,015,204 | | 1997 | 5,688,176 | | 1996 | 5,041,165 | | 1995 | 4,459,281 | | 1994 | 4,984,740 | | 1993 | 4,742,803 | | 1992 | 4,522,116 | | 1991 | 4,422,891 |
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