Year Grams per day 1961 33.79 1962 33.9 1963 33.33 1964 33.4 1965 35.14 1966 37.18 1967 38.69 1968 40.09 1969 42.89 1970 46.2 1971 50.33 1972 49.41 1973 49.83 1974 49.15 1975 42.86 1976 45.89 1977 49.14 1978 50.53 1979 51.47 1980 55.83 1981 51.23 1982 56.17 1983 57.68 1984 54 1985 54.81 1986 55.23 1987 56.93 1988 53.28 1989 49.55 1990 46.43 1991 44.38 1992 40.41 1993 39.65 1994 39.09 1995 38.09 1996 37.03 1997 32.03 1998 36.61 1999 37.11 2000 42.95 2001 45.48 2002 52.63 2003 53.68 2004 58.15 2005 65.34 2006 66.39 2007 63.45 2008 63.77 2009 65.85 2010 65.49 2011 67.37 2012 96.37 2013 96.14