| Year | Value | | 2025 | 36,818,130 | | 2024 | 36,409,307 | | 2023 | 35,554,975 | | 2022 | 35,081,594 | | 2021 | 33,490,693 | | 2020 | 31,770,146 | | 2019 | 33,686,201 | | 2018 | 33,302,540 | | 2017 | 32,535,361 | | 2016 | 31,514,194 | | 2015 | 30,550,902 | | 2014 | 29,521,920 | | 2013 | 29,149,709 | | 2012 | 28,126,488 | | 2011 | 27,575,358 | | 2010 | 26,452,690 | | 2009 | 25,413,653 | | 2008 | 24,405,474 | | 2007 | 23,635,212 | | 2006 | 23,497,202 | | 2005 | 23,212,611 | | 2004 | 22,775,376 | | 2003 | 23,365,651 | | 2002 | 23,537,756 | | 2001 | 23,207,086 | | 2000 | 22,804,910 | | 1999 | 23,563,397 | | 1998 | 23,094,059 | | 1997 | 22,467,652 | | 1996 | 22,434,274 | | 1995 | 22,054,066 | | 1994 | 21,720,314 | | 1993 | 20,211,005 | | 1992 | 21,160,763 | | 1991 | 21,015,986 | | 1990 | 20,354,848 |
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