Year	Percent
1995	23.02673
1996	23.15151
1997	23.27854
1998	22.68919
1999	22.18766
2000	22.11624
2001	20.54145
2002	20.20604
2003	20.51968
2004	20.33666
2005	20.56944
2006	21.38766
2007	21.2231
2008	20.69286
2009	20.23888
2010	20.41955
2011	19.57159
2012	19.97544
2013	19.84517
2014	19.60038
2015	18.80231
2016	18.67231