Year	Grams per day
1961	2.04
1962	2.91
1963	2.68
1964	2.54
1965	2.82
1966	2.51
1967	3.06
1968	5.11
1969	5.11
1970	5.27
1971	4.58
1972	2.81
1973	2.51
1974	1.67
1975	3.13
1976	3.01
1977	4.38
1978	4.33
1979	3.35
1980	1.25
1981	3.14
1982	1.86
1983	2.5
1984	2.67
1985	2.43
1986	1.99
1987	2.44
1988	3.31
1989	5.77
1990	5.96
1991	7.87
1992	5.96
1993	7.72
1994	9.92
1995	10.89
1996	10.11
1997	9.93
1998	11.13
1999	12.77
2000	12.15
2001	12.77
2002	11.87
2003	12.17
2004	10.92
2005	14.37
2006	14.53
2007	16.55
2008	17.06
2009	16.87
2010	16.3
2011	17.73
2012	19.09
2013	19.7