Year	Grams per day
1961	13.98
1962	16.36
1963	18.77
1964	18.69
1965	17.76
1966	17.95
1967	20.2
1968	17.81
1969	15.94
1970	20.23
1971	16.91
1972	21.56
1973	19.57
1974	17.4
1975	16.66
1976	18.16
1977	17.32
1978	16.97
1979	17.86
1980	12.93
1981	12.16
1982	13.94
1983	16.58
1984	13.06
1985	24.18
1986	17.65
1987	12.67
1988	13.37
1989	19.3
1990	24.02
1991	15.47
1992	14.78
1993	16.92
1994	15.69
1995	18.47
1996	24.13
1997	18.16
1998	22.23
1999	17.23
2000	20.19
2001	19.47
2002	20.57
2003	19.6
2004	23.09
2005	25.09
2006	25.18
2007	24.91
2008	22.42
2009	21.26
2010	25.29
2011	27.92
2012	30.46
2013	29.05