Year	Percent
1983	2.73
1984	3.15
1985	3.52
1986	2.42
1987	3.46
1988	2.75
1989	2.57
1990	3.08
1991	2.86
1992	2.99
1993	3.09
1994	4.44
1995	2.11
1996	3.97
1997	2.03
1999	0.59
2000	0.37
2002	0.68
2003	0.5
2004	0.94
2006	0.38