Year	Grams per day
1961	17.35
1962	16.72
1963	16.84
1964	17.19
1965	17.85
1966	19.42
1967	26.97
1968	32.56
1969	34.47
1970	38.6
1971	43.15
1972	41.72
1973	43.72
1974	40.12
1975	44.32
1976	41.92
1977	39.82
1978	36.76
1979	43.06
1980	50.65
1981	50.74
1982	51.6
1983	48.94
1984	48.28
1985	47.35
1986	43.17
1987	48.43
1988	46.01
1989	46.02
1990	46.53
1991	45.69
1992	45.12
1993	44.5
1994	40.56
1995	41.05
1996	35.07
1997	40.41
1998	31.39
1999	31.03
2000	44.23
2001	31.17
2002	34.83
2003	32.82
2004	31.88
2005	29.98
2006	31.21
2007	27.03
2008	26.4
2009	28.48
2010	28
2011	28.44
2012	30.06
2013	28.13