Year Total 1970 5418000 1971 5653200 1972 5554200 1973 5747700 1974 5679700 1975 6449100 1976 6644200 1977 6720700 1978 6367800 1979 7488600 1980 8548000 1981 8545400 1982 9272700 1983 10619000 1984 11520000 1985 11952000 1986 14001000 1987 14284000 1988 16889000 1989 17976000 1990 17016000 1991 18240000 1992 18891000 1993 18946000 1994 19557000 1995 21577000 1996 23836000 1997 24973000 1998 26954000 1999 30759000 2000 34322000 2001 34226000 2002 33712000 2003 37620000 2004 40392000 2005 41067000 2006 41490000 2007 40347000 2008 39654000 2009 37283000 2010 36089000 2011 34906000 2012 33956000 2013 31980000 2014 31907000 2015 32842000 2016 34443000