Year	Percent
1995	19.15703
1996	17.59347
1997	18.10831
1998	18.64425
1999	16.86747
2000	16.6123
2001	16.36531
2002	15.95815
2003	16.15927
2004	15.64846
2005	14.69479
2006	13.63801
2007	14.86946
2008	13.37648
2009	11.522
2010	11.42775
2011	11.18867
2012	10.67072
2013	10.90497
2014	11.29321
2015	11.36615
2016	11.69455
2017	11.5757