| Year | Value | | 2022 | 23,331,867 | | 2021 | 22,533,249 | | 2020 | 21,734,692 | | 2019 | 20,945,941 | | 2018 | 20,189,123 | | 2017 | 19,471,441 | | 2016 | 18,793,039 | | 2015 | 18,150,223 | | 2014 | 17,535,276 | | 2013 | 16,938,360 | | 2012 | 16,359,854 | | 2011 | 15,807,262 | | 2010 | 15,297,271 | | 2009 | 14,824,506 | | 2008 | 14,368,194 | | 2007 | 13,960,493 | | 2006 | 13,582,272 | | 2005 | 13,176,705 | | 2004 | 12,770,271 | | 2003 | 12,376,238 | | 2002 | 11,978,960 | | 2001 | 11,617,658 | | 2000 | 11,308,441 | | 1999 | 11,011,761 | | 1998 | 10,720,938 | | 1997 | 10,443,721 | | 1996 | 10,174,025 | | 1995 | 9,883,577 | | 1994 | 9,507,885 | | 1993 | 9,117,055 | | 1992 | 8,806,708 | | 1991 | 8,569,656 | | 1990 | 8,392,286 | | 1989 | 8,241,975 | | 1988 | 8,097,670 | | 1987 | 7,928,923 | | 1986 | 7,733,107 | | 1985 | 7,535,847 | | 1984 | 7,346,659 | | 1983 | 7,173,885 | | 1982 | 7,022,697 | | 1981 | 6,905,513 | | 1980 | 6,797,618 | | 1979 | 6,663,422 | | 1978 | 6,513,962 | | 1977 | 6,369,996 | | 1976 | 6,240,553 | | 1975 | 6,113,831 | | 1974 | 5,984,772 | | 1973 | 5,853,793 | | 1972 | 5,723,986 | | 1971 | 5,595,915 | | 1970 | 5,466,495 | | 1969 | 5,342,152 | | 1968 | 5,225,844 | | 1967 | 5,115,165 | | 1966 | 5,009,946 | | 1965 | 4,908,272 | | 1964 | 4,808,973 | | 1963 | 4,710,699 | | 1962 | 4,612,657 | | 1961 | 4,515,153 | | 1960 | 4,419,355 |
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