Year Grams per day 1961 48.62 1962 49.2 1963 50.14 1964 51.77 1965 56.63 1966 66.4 1967 65.8 1968 66.13 1969 68.17 1970 67.87 1971 64.58 1972 51.93 1973 44.26 1974 21.02 1975 12.63 1976 15 1977 23.86 1978 39.67 1979 51.81 1980 47.67 1981 43.55 1982 40.89 1983 49.36 1984 52.76 1985 64.15 1986 64.01 1987 60.02 1988 55.38 1989 62.33 1990 51.64 1991 67.65 1992 66.61 1993 52.01 1994 70.38 1995 51.58 1996 66.2 1997 77.85 1998 85.71 1999 74.33 2000 85.19 2001 83.76 2002 85.87 2003 78.48 2004 75.97 2005 72.42 2006 83.01 2007 72.18 2008 88.19 2009 69.83 2010 79.4 2011 75.43 2012 74.55 2013 73.37