Year per Person 1965 18.73952 1966 17.57126 1967 17.8504 1968 17.62177 1969 16.98279 1970 17.02141 1971 15.90577 1972 14.14649 1973 14.35708 1974 12.36337 1975 9.51277 1976 9.08426 1977 8.59937 1978 8.05318 1979 8.53015 1980 7.64798 1981 7.20857 1982 6.33885 1983 5.85346 1984 5.72196 1985 5.22639 1986 5.50657 1987 5.4372 1988 5.56245 1989 5.44967 1990 5.93094 1991 6.45925 1992 6.32672 1993 6.40254 1994 6.64999 1995 7.00042 1996 7.29268 1997 7.42184 1998 7.54239 1999 6.61959 2000 6.54556 2001 6.53467 2002 6.00975 2003 5.70114 2004 6.46327 2005 6.32501 2006 6.2836 2007 5.97791 2008 5.88344 2009 5.45801 2010 5.02411 2011 4.80293 2012 4.66061 2013 4.54452 2014 4.50609 2015 4.36365 2016 3.92991