Year Total 1965 3777000 1966 3878000 1967 4335000 1968 4936000 1969 4632000 1970 4581000 1971 4290000 1972 3554000 1973 3641000 1974 3921000 1975 4066000 1976 4061000 1977 4270000 1978 4497000 1979 4794000 1980 5012000 1981 5328000 1982 5869000 1983 6476000 1984 7028000 1985 7506000 1986 8084000 1987 8849000 1988 9530000 1989 10215000 1990 10694000 1991 11269000 1992 12334000 1993 13459000 1994 14440000 1995 15663000 1996 16485000 1997 17007000 1998 17594000 1999 18222000 2000 18836000 2001 18463000 2002 17978000 2003 15905000 2004 16038000 2005 15238000 2006 17580000 2007 19140000 2008 19417000 2009 20749000 2010 20548000 2011 20677000 2012 19991000 2013 21910000 2014 22649000 2015 24585000 2016 27472000