Year	Percent
1995	26.1
1996	29.3
1997	29.5
1998	30.7
1999	29.8
2000	25.7
2001	27.6
2002	25.69
2003	26.9
2004	24.7
2005	26
2006	27.3
2007	22.7
2009	23.52
2010	23.83
2011	22.64
2012	22.85
2013	26.15
2016	23.8