Year	2007 US$
1980	12.35
1981	20.65
1982	21.35
1983	7.257
1984	14.29
1985	17.34
1986	15.44
1987	14.61
1988	13.92
1989	28.82
1990	41.15
1991	51.2
1992	56.76
1993	57.81
1994	58.54
1995	53.58
1996	48.77
1997	54.23
1998	60.1
1999	60.27
2000	58.59
2001	83.41
2002	73.24
2003	64.79
2004	69.58
2005	82.59
2006	95.98
2007	113.7