Year	Grams per day
1961	4.54
1962	5.52
1963	4.24
1964	3.83
1965	5.4
1966	5.4
1967	6.89
1968	4.26
1969	6.29
1970	6.94
1971	9.63
1972	8.41
1973	9
1974	6.15
1975	7.97
1976	12.12
1977	19.1
1978	24.39
1979	25.06
1980	30.55
1981	32.57
1982	28.26
1983	28.58
1984	17.95
1985	16.03
1986	17.19
1987	22.39
1988	13.62
1989	12.56
1990	12.49
1991	16.59
1992	16.98
1993	18.11
1994	14.01
1995	22.1
1996	16.98
1997	19.72
1998	22.01
1999	22.18
2000	22.02
2001	29.23
2002	29.19
2003	28.46
2004	28.76
2005	27.47
2006	25.58
2007	26.12
2008	26.83
2009	27.86
2010	28.43
2011	25.94
2012	28.54
2013	29.45