Year	Grams per day
1961	4.77
1962	6.48
1963	7.67
1964	6.61
1965	9.78
1966	9.68
1967	9.64
1968	8.75
1969	8.94
1970	11.18
1971	13.1
1972	13.36
1973	14.64
1974	11.64
1975	8.04
1976	13.67
1977	16.35
1978	17.63
1979	18.11
1980	15.57
1981	15.07
1982	13.99
1983	19.79
1984	18.49
1985	15.7
1986	19.17
1987	19.75
1988	23.15
1989	19.34
1990	12.54
1991	11.9
1992	12
1993	15.33
1994	14.59
1995	15.24
1996	11.31
1997	13.43
1998	16.26
1999	12.5
2000	13.04
2001	13.39
2002	14.22
2003	13.59
2004	14.46
2005	15.07
2006	16.19
2007	16.26
2008	16.78
2009	19.03
2010	19.9
2011	19.93
2012	14.47
2013	15.48