Year	Percent
1994	40.26307
1995	38.05897
1996	36.46176
1997	35.04176
1998	34.46826
1999	42.87554
2000	31.50269
2001	29.57764
2002	26.16851
2003	28.80544
2004	26.59845
2005	25.69022
2006	23.52498
2007	21.88419
2008	20.55743
2009	20.70389
2010	21.55816
2011	17.80916
2012	21.08711
2013	21.70006
2014	18.99242
2015	21.12681
2016	21.05663
2017	22.80023