Year	Grams per day
1961	0
1962	0
1963	0.09
1964	0.44
1965	0.83
1966	1.68
1967	2.72
1968	3.76
1969	3.4
1970	2.63
1971	1.39
1972	1.07
1973	1
1974	1.41
1975	1.24
1976	1.71
1977	1.67
1978	2.39
1979	3.75
1980	5.29
1981	5.14
1982	4.73
1983	4.22
1984	5.55
1985	4.9
1986	4.72
1987	4.99
1988	5.47
1989	5.48
1990	4.61
1991	4.68
1992	4.72
1993	5.35
1994	4.89
1995	4.61
1996	5.14
1997	9.94
1998	9.65
1999	7.18
2000	3.97
2001	7.64
2002	6.02
2003	5.48
2004	3.29
2005	5.21
2006	8.2
2007	10.01
2008	8.79
2009	11.88
2010	14.93
2011	14.31
2012	18.9
2013	14.09