| Year | Value | | 2023 | 25,784,506 | | 2022 | 26,172,633 | | 2021 | 26,577,264 | | 2020 | 26,973,587 | | 2019 | 27,334,331 | | 2018 | 27,682,266 | | 2017 | 28,025,949 | | 2016 | 28,365,184 | | 2015 | 28,698,428 | | 2014 | 29,028,350 | | 2013 | 29,356,925 | | 2012 | 29,683,011 | | 2011 | 30,013,311 | | 2010 | 30,343,407 | | 2009 | 30,648,277 | | 2008 | 30,936,590 | | 2007 | 31,209,180 | | 2006 | 31,464,114 | | 2005 | 31,703,559 | | 2004 | 31,929,788 | | 2003 | 32,145,420 | | 2002 | 32,344,831 | | 2001 | 32,522,283 | | 2000 | 32,729,358 | | 1999 | 33,476,967 | | 1998 | 34,202,391 | | 1997 | 34,918,951 | | 1996 | 35,628,669 | | 1995 | 36,212,483 | | 1994 | 36,785,438 | | 1993 | 37,346,900 | | 1992 | 37,883,788 | | 1991 | 38,401,409 | | 1990 | 38,893,570 | | 1989 | 39,352,163 | | 1988 | 39,779,494 | | 1987 | 40,173,989 | | 1986 | 40,528,406 | | 1985 | 40,841,690 | | 1984 | 41,110,982 | | 1983 | 41,348,523 | | 1982 | 41,552,102 | | 1981 | 41,722,424 | | 1980 | 41,855,360 | | 1979 | 41,964,817 | | 1978 | 42,049,843 | | 1977 | 42,114,900 | | 1976 | 42,162,117 | | 1975 | 42,198,708 |
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