Year	Percent
2000	52.48081
2001	54.00237
2002	55.52394
2003	57.0455
2004	58.56706
2005	60.08863
2006	61.61019
2007	63.13175
2008	64.65332
2009	66.17488
2010	67.69644
2011	69.218
2012	70.73957
2013	72.26113
2014	72.26113
2015	72.26113