Year	Grams per day
1961	7.24
1962	7.66
1963	7.45
1964	10.04
1965	9.78
1966	10.5
1967	12.03
1968	13.05
1969	14.15
1970	16.39
1971	19.58
1972	17.6
1973	17.96
1974	16.63
1975	16.26
1976	18.22
1977	17.42
1978	17.78
1979	18.89
1980	21.78
1981	22.8
1982	21.67
1983	22.31
1984	23.68
1985	24.06
1986	25.99
1987	28.52
1988	33.15
1989	32.12
1990	36.36
1991	41.05
1992	40.55
1993	36.48
1994	41.42
1995	44.8
1996	42.21
1997	42.75
1998	37.34
1999	33.99
2000	31.13
2001	33.27
2002	33.66
2003	34.06
2004	34.25
2005	34.14
2006	34.42
2007	34.48
2008	36.89
2009	32.38
2010	33.83
2011	21.93
2012	32.04
2013	22.62