Year	Percent
1995	26.92784
1996	26.06201
1997	26.93662
1998	25.33171
1999	24.43467
2000	24.41838
2001	24.02826
2002	23.56124
2003	24.15845
2004	25.24367
2005	24.57807
2006	24.31229
2007	23.90524
2008	23.82273
2009	23.88573
2010	23.14118
2011	23.27773
2012	22.98412
2013	22.46488
2014	22.50405
2015	22.34186
2016	22.13847
2017	21.76103