Year	Grams per day
1961	7.55
1962	16.56
1963	9.57
1964	7.94
1965	15.87
1966	11.76
1967	9.16
1968	18.18
1969	9.28
1970	20.28
1971	16.29
1972	13.68
1973	18.98
1974	13.87
1975	12.5
1976	18.47
1977	8.91
1978	9.07
1979	13.31
1980	17.79
1981	12.08
1982	8.94
1983	8.27
1984	12.86
1985	13.1
1986	18.05
1987	16.16
1988	17.44
1989	27.57
1990	25.31
1991	31.84
1992	27.19
1993	22.87
1994	34.73
1995	27.19
1996	39.88
1997	28.57
1998	38.6
1999	37.94
2000	38.38
2001	37.85
2002	39.6
2003	36.84
2004	35.59
2005	35.23
2006	37.62
2007	36.56
2008	36.97
2009	34.79
2010	29.37
2011	25.42
2012	36.09
2013	28.12