Year Number 1970 1335900 1971 1085600 1972 625200 1973 805200 1974 1047700 1975 1451800 1976 1947400 1977 2303700 1978 2656300 1979 2773100 1980 3029200 1981 3096800 1982 3328800 1983 3466900 1984 3641900 1985 3839400 1986 4127200 1987 4434400 1988 4889400 1989 5009000 1990 5180200 1991 5197700 1992 5680600 1993 5647100 1994 5663700 1995 5342600 1996 5375000 1997 5882500 1998 5414100 1999 5850000 2000 5293541 2001 6011849 2002 4141009 2003 4522110 2004 5097477 2005 5364134 2006 5714831 2007 5439144 2008 5605758 2009 5303268 2010 6588114 2011 7940545.07551206 2012 7973906.36067277 2013 7833901.08773203 2014 7670348.18543139 2015 8467827 2016 9628354 2017 7260769 2018 6880637 2019 7420378.249 2020 3711456.87 2021 4930661.98