Year	Grams per day
1961	5.41
1962	5
1963	5.4
1964	6.57
1965	7
1966	7.23
1967	6.56
1968	7.21
1969	7.36
1970	7.17
1971	6.94
1972	7.7
1973	8.25
1974	7.74
1975	7.87
1976	8.07
1977	9.79
1978	10.08
1979	11.47
1980	13.25
1981	13.14
1982	17.24
1983	15.42
1984	17
1985	18.96
1986	17.54
1987	19.15
1988	21.67
1989	18.61
1990	18.73
1991	21.32
1992	18.88
1993	14.01
1994	15.65
1995	18.13
1996	20.32
1997	22.83
1998	22.29
1999	17.05
2000	15.73
2001	16.54
2002	15.73
2003	17.38
2004	16.71
2005	16.93
2006	17.16
2007	17.73
2008	17.49
2009	18.02
2010	17.9
2011	18.75
2012	18.89
2013	18.76