Year	%
1998	61.96638
1999	61.8305
2000	63.13888
2001	66.31338
2002	68.63993
2003	69.25561
2004	69.12484
2005	70.06812
2006	71.77648
2007	71.7867
2008	72.96055
2009	73.83126
2010	73.39016
2011	75.27195
2012	73.58848
2013	75.29831
2014	74.28438
2015	76.91396
2016	75.61712
2017	77.24945