Year	Percent
1994	33.7002
1995	36.32575
1996	35.34257
1997	30.90161
1998	31.63254
1999	34.73031
2000	36.46361
2001	39.55858
2002	37.78282
2003	36.62888
2004	37.27309
2005	31.58957
2006	25.26386
2007	32.18027
2008	30.53553
2009	26.87038
2010	30.87499
2011	35.74262
2012	39.01732
2013	44.11444
2014	41.24113
2015	42.7267
2016	38.63391
2017	36.38919