Year	Percent
1998	93.97589
1999	94.59305
2000	94.85548
2001	93.90308
2002	93.46086
2003	94.11603
2004	94.36369
2005	94.16798
2006	93.77688
2007	94.48085
2008	94.725
2009	94.80455
2010	95.35359
2011	95.19496
2012	94.81235
2013	94.13797
2014	93.82575
2015	93.62683
2016	93.31708
2017	93.50452