Year Number 1970 2671600 1971 2554000 1972 3285800 1973 3391600 1974 3037300 1975 3839900 1976 4534000 1977 5147500 1978 6099600 1979 6546800 1980 6603100 1981 7574500 1982 8391700 1983 9164800 1984 10125700 1985 10993800 1986 11785200 1987 12668600 1988 12863100 1989 12740100 1990 10862200 1991 10717400 1992 11127100 1993 9441600 1994 11518400 1995 14260600 1996 13394600 1997 16039800 1998 16521000 1999 16005400 2000 17299483 2001 16862737 2002 17633019 2003 19455085 2004 23934074 2005 27879461 2006 40288794 2007 51897450 2008 49877935 2009 54446373 2010 64374253.8038964 2011 73996912 2012 72151828.8895485 2013 75589071 2014 82718882.88 2015 98927860 2016 119577835 2017 139752424 2018 164035637.545 2019 167499116 2020 68959633 2021 83964797