Year Grams per day 1961 98.14 1962 85.54 1963 97.3 1964 71.69 1965 93.22 1966 79.29 1967 101.96 1968 91.81 1969 68.51 1970 90.44 1971 90.22 1972 95.86 1973 109.47 1974 106.57 1975 100.13 1976 104.04 1977 105.08 1978 98.33 1979 81.46 1980 86.53 1981 85.17 1982 91.94 1983 88.35 1984 84.04 1985 87.74 1986 91.48 1987 84.85 1988 85.63 1989 85.63 1990 83.43 1991 81.66 1992 81.13 1993 79.15 1994 79.75 1995 81.08 1996 75.86 1997 74.96 1998 76.22 1999 73.37 2000 73.16 2001 72.22 2002 73.5 2003 74.59 2004 73.09 2005 73.45 2006 74.72 2007 79.42 2008 82.14 2009 80.57 2010 83.38 2011 84.69 2012 90.61 2013 92.98