Year	Percent
1995	29.77866
1996	30.1879
1997	30.92974
1998	31.27521
1999	31.06635
2000	30.58357
2001	30.60426
2002	30.12716
2003	30.37593
2004	30.3924
2005	29.94793
2006	30.32118
2007	30.80809
2008	29.89775
2009	27.4592
2010	26.66301
2011	26.90477
2012	27.47552
2013	27.59708
2014	28.37089
2015	28.15653
2016	27.98284
2017	28.76806