Year	Percent
1975	40.21593
1976	40.3234
1979	42.12083
1982	42.65104
1986	38.22622
2001	59.8159
2002	61.72572
2003	61.24335
2004	57.47301
2005	56.04879
2007	51.93144
2008	56.48351
2009	72.52605
2010	55.07815
2011	52.84995
2012	53.92312
2013	53.88423
2014	57.15273
2016	52.61005