Year	Percent
1999	26.47
2000	32.61
2001	31.61
2002	39.12
2006	49.35
2007	46.99
2008	50.04
2009	54.84
2011	51.44
2012	56.51
2013	54.76
2014	57.95
2015	56.05
2016	46.33