| Year | Value | | 2022 | 27,249,938 | | 2021 | 26,726,429 | | 2020 | 26,205,082 | | 2019 | 25,679,257 | | 2018 | 25,168,522 | | 2017 | 24,652,004 | | 2016 | 24,114,618 | | 2015 | 23,582,948 | | 2014 | 23,061,826 | | 2013 | 22,533,107 | | 2012 | 21,992,229 | | 2011 | 21,439,190 | | 2010 | 20,875,000 | | 2009 | 20,296,096 | | 2008 | 19,707,234 | | 2007 | 19,133,373 | | 2006 | 18,579,218 | | 2005 | 18,040,263 | | 2004 | 17,517,645 | | 2003 | 17,008,340 | | 2002 | 16,517,681 | | 2001 | 16,030,683 | | 2000 | 15,558,445 | | 1999 | 15,116,098 | | 1998 | 14,701,779 | | 1997 | 14,313,761 | | 1996 | 13,937,256 | | 1995 | 13,566,081 | | 1994 | 13,191,070 | | 1993 | 12,817,038 | | 1992 | 12,445,537 | | 1991 | 12,073,477 | | 1990 | 11,692,664 | | 1989 | 11,302,974 | | 1988 | 10,919,898 | | 1987 | 10,545,806 | | 1986 | 10,183,316 | | 1985 | 9,826,764 | | 1984 | 9,474,893 | | 1983 | 9,130,745 | | 1982 | 8,799,162 | | 1981 | 8,483,287 | | 1980 | 8,181,266 | | 1979 | 7,895,961 | | 1978 | 7,626,855 | | 1977 | 7,369,217 | | 1976 | 7,129,546 | | 1975 | 6,902,776 | | 1974 | 6,676,963 | | 1973 | 6,452,684 | | 1972 | 6,231,008 | | 1971 | 6,015,733 | | 1970 | 5,800,300 | | 1969 | 5,580,984 | | 1968 | 5,365,508 | | 1967 | 5,156,435 | | 1966 | 4,954,536 | | 1965 | 4,759,032 | | 1964 | 4,571,212 | | 1963 | 4,393,111 | | 1962 | 4,223,183 | | 1961 | 4,061,910 | | 1960 | 3,910,535 |
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