Year	Grams per day
1961	5.65
1962	7.18
1963	7.74
1964	10.01
1965	8.34
1966	12.42
1967	11.95
1968	11.96
1969	12.74
1970	12.16
1971	11.7
1972	12.5
1973	12.2
1974	21.78
1975	47.01
1976	43.86
1977	53.28
1978	50.33
1979	54.96
1980	56.47
1981	62.75
1982	63.15
1983	60.47
1984	61.46
1985	59.24
1986	62.32
1987	60.76
1988	59.27
1989	57.9
1990	52.26
1991	40.86
1992	40.19
1993	46.69
1994	43.43
1995	44.38
1996	46.7
1997	47.02
1998	50.06
1999	49.01
2000	43.1
2001	42.29
2002	43.56
2003	44.8
2004	45.15
2005	43.66
2006	43.03
2007	43.63
2008	39.73
2009	43.45
2010	44.38
2011	44.78
2012	41.68
2013	42.62