| Year | Value | | 2022 | 21,726,459 | | 2021 | 20,977,713 | | 2020 | 20,286,946 | | 2019 | 19,626,297 | | 2018 | 18,993,525 | | 2017 | 18,375,072 | | 2016 | 17,772,670 | | 2015 | 17,174,716 | | 2014 | 16,579,805 | | 2013 | 16,007,928 | | 2012 | 15,459,233 | | 2011 | 14,929,599 | | 2010 | 14,414,736 | | 2009 | 13,913,754 | | 2008 | 13,433,141 | | 2007 | 12,976,080 | | 2006 | 12,550,724 | | 2005 | 12,166,260 | | 2004 | 11,818,553 | | 2003 | 11,503,256 | | 2002 | 11,215,013 | | 2001 | 10,940,554 | | 2000 | 10,667,413 | | 1999 | 10,381,212 | | 1998 | 10,094,131 | | 1997 | 9,846,263 | | 1996 | 9,640,696 | | 1995 | 9,450,164 | | 1994 | 9,279,053 | | 1993 | 9,115,728 | | 1992 | 8,916,096 | | 1991 | 8,680,123 | | 1990 | 8,435,273 | | 1989 | 8,196,045 | | 1988 | 7,982,851 | | 1987 | 7,788,934 | | 1986 | 7,597,175 | | 1985 | 7,433,257 | | 1984 | 7,292,512 | | 1983 | 7,151,734 | | 1982 | 7,005,362 | | 1981 | 6,854,882 | | 1980 | 6,725,362 | | 1979 | 6,597,650 | | 1978 | 6,446,350 | | 1977 | 6,301,629 | | 1976 | 6,169,674 | | 1975 | 6,035,743 | | 1974 | 5,900,637 | | 1973 | 5,767,081 | | 1972 | 5,637,618 | | 1971 | 5,512,216 | | 1970 | 5,389,916 | | 1969 | 5,276,380 | | 1968 | 5,168,583 | | 1967 | 5,062,509 | | 1966 | 4,957,863 | | 1965 | 4,851,697 | | 1964 | 4,744,470 | | 1963 | 4,640,351 | | 1962 | 4,539,699 | | 1961 | 4,441,044 | | 1960 | 4,349,400 |
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