Year	US Dollars
1996	4.81
1997	5.55
1998	5.87
1999	5.2
2000	5.5
2001	5.9
2002	6.63
2003	7.06
2004	7.49
2005	8.13
2006	9.28
2007	11.09
2009	15.13
2010	15.67
2011	16.19
2012	17.64
2013	18.73
2014	19.98
2015	20.3
2016	21.2