Year	Percent
1992	67.04807
1994	67.92522
1998	90.94856
1999	90.16003
2000	85.76229
2001	90.38395
2002	87.20142
2003	88.48075
2004	80.76815
2005	81.69268
2006	78.47305
2008	74.29214
2009	80.71477
2010	77.96585
2012	83.03298
2013	84.00164