Year	US Dollars adjusted for inflation)
1989	11.4
1990	11.07
1991	10.19
1992	8.21
1993	7.18
1994	6.94
1995	7.35
1996	7.66
1997	8.25
1998	8.68
1999	9.02
2000	9.17
2001	10.25
2002	10.74
2003	11.7
2004	12.4
2005	12.58
2006	13.41