Year	Percent
2000	66.72945
2001	68.29329
2002	69.86859
2003	71.45503
2004	73.05254
2005	74.66081
2006	76.27974
2007	77.9089
2008	79.54833
2009	81.19771
2010	82.85683
2011	84.5255
2012	86.2035
2013	87.89055
2014	89.5866
2015	89.61494
2016	89.64348
2017	89.67217
2018	89.70106