Year	Grams per day
1992	27.69
1993	25.59
1994	28.99
1995	28.94
1996	33.09
1997	42.17
1998	39.53
1999	38.98
2000	37
2001	45.7
2002	45.95
2003	41.04
2004	44.3
2005	46.36
2006	52.41
2007	57.05
2008	59.28
2009	52.43
2010	53.77
2011	55.38
2012	57.67
2013	55.26