| Year | Value | | 2023 | 9,558,863 | | 2022 | 9,481,264 | | 2021 | 9,308,917 | | 2020 | 9,183,306 | | 2019 | 9,226,063 | | 2018 | 9,164,074 | | 2017 | 9,113,763 | | 2016 | 9,066,824 | | 2015 | 9,019,041 | | 2014 | 8,968,071 | | 2013 | 8,913,429 | | 2012 | 8,857,279 | | 2011 | 8,798,238 | | 2010 | 8,725,678 | | 2009 | 8,642,962 | | 2008 | 8,502,563 | | 2007 | 8,262,978 | | 2006 | 8,071,657 | | 2005 | 7,926,592 | | 2004 | 7,852,764 | | 2003 | 7,751,505 | | 2002 | 7,659,421 | | 2001 | 7,605,947 | | 2000 | 7,584,451 | | 1999 | 7,580,212 | | 1998 | 7,599,491 | | 1997 | 7,651,423 | | 1996 | 7,712,652 | | 1995 | 7,790,956 | | 1994 | 7,905,663 | | 1993 | 7,956,288 | | 1992 | 7,934,441 | | 1991 | 7,907,995 |
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