Year	Percent
1995	25.08098
1996	24.73728
1997	25.90535
1998	26.91506
1999	28.85536
2000	28.52064
2001	26.37629
2002	25.34935
2003	26.4218
2004	28.60556
2005	28.37993
2006	30.17775
2007	32.87602
2008	32.6949
2009	23.38212
2010	22.23995
2011	21.72006
2012	18.70642
2013	19.48491
2014	19.58446
2015	19.37066
2016	18.70051
2017	19.28643