Year	Percent
1990	99.2
1991	96.6
1992	96.7
1993	96.7
1994	97
1995	96.7
1996	96.7
1997	96.8
1998	96.8
2003	91.27
2004	90.12
2005	89.97
2006	88.98
2007	89.04
2008	90.52
2009	93.56