Year Total 1965 13765000 1966 14644000 1967 15962000 1968 17488000 1969 18107000 1970 20001000 1971 21571000 1972 22218000 1973 21601000 1974 21145000 1975 20261000 1976 20414000 1977 22062000 1978 23210000 1979 24278000 1980 25267000 1981 25736000 1982 25571000 1983 25667000 1984 25142000 1985 24159000 1986 22869000 1987 22573000 1988 23720000 1989 24230000 1990 25437000 1991 25882000 1992 29040000 1993 31068000 1994 34511000 1995 37457000 1996 40816000 1997 43386000 1998 44028000 1999 41684000 2000 41379000 2001 43987000 2002 43329000 2003 43171000 2004 41113000 2005 39446000 2006 39525000 2007 38257000 2008 37823000 2009 34009000 2010 33349000 2011 30920000 2012 31061000 2013 30485000 2014 29881000 2015 29832000 2016 28799000