Year	Percent
1991	38.98305
1992	67.125
1993	84.69561
1994	84.95528
1995	83.97293
1996	74.58133
1997	42.68831
1998	32.65932
1999	56.13937
2000	95.50163
2001	81.39139
2002	69.0493
2003	62.30928
2004	61.65229
2005	65.02676
2006	73.09101
2007	75.39384
2008	64.05825
2009	74.59539
2010	76.31547
2011	74.69609
2012	73.2581