Year Total 1970 10123000 1971 10020000 1972 10439000 1973 11350000 1974 11903000 1975 12089000 1976 11878000 1977 12586000 1978 15757000 1979 19141000 1980 23137000 1981 24907000 1982 26619000 1983 26803000 1984 26369000 1985 25619000 1986 22779000 1987 23151000 1988 23458000 1989 22515000 1990 24408000 1991 24749000 1992 23963000 1993 25659000 1994 27336000 1995 26993000 1996 29429000 1997 31106000 1998 33688000 1999 33823000 2000 34488000 2001 34612000 2002 35762000 2003 37459000 2004 39029000 2005 47006000 2006 51572000 2007 48195000 2008 48042000 2009 53346000 2010 51806000 2011 52426000 2012 51473000 2013 52369000 2014 51358000 2015 48653000 2016 42461000