Year	Percent
1999	12.99175
2000	14.10037
2001	12.06136
2002	13.0987
2003	13.65448
2004	13.27566
2005	17.12308
2006	17.74755
2007	16.4846
2008	17.86266
2009	16.37177
2010	15.57052
2011	18.51505
2012	18.31656
2013	17.56138
2014	17.29435
2015	20.45137
2016	19.64812