| Year | Value | | 2023 | 31,790,395 | | 2022 | 31,616,935 | | 2021 | 31,271,173 | | 2020 | 30,379,167 | | 2019 | 30,652,293 | | 2018 | 30,691,326 | | 2017 | 30,547,530 | | 2016 | 30,573,605 | | 2015 | 30,521,969 | | 2014 | 30,406,445 | | 2013 | 30,427,131 | | 2012 | 30,175,391 | | 2011 | 29,908,458 | | 2010 | 29,884,514 | | 2009 | 29,790,243 | | 2008 | 29,512,889 | | 2007 | 29,300,012 | | 2006 | 29,052,914 | | 2005 | 28,867,248 | | 2004 | 28,778,198 | | 2003 | 28,620,674 | | 2002 | 28,039,182 | | 2001 | 27,705,599 | | 2000 | 27,582,517 | | 1999 | 27,398,160 | | 1998 | 27,090,955 | | 1997 | 26,942,696 | | 1996 | 26,937,253 | | 1995 | 26,614,451 | | 1994 | 26,472,563 | | 1993 | 26,351,924 | | 1992 | 26,197,039 | | 1991 | 25,965,659 |
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