Year	Percent
1993	20.32122
1994	16.53151
1995	12.25572
1996	16.70297
1997	32.18329
1998	12.20066
1999	44.04953
2000	25.53706
2001	24.16356
2002	15.11733
2003	21.92879
2004	24.2839
2005	31.90905
2006	29.11836
2007	42.10468
2008	15.38386
2009	35.93889
2010	39.18156
2011	23.67193
2012	36.06452
2013	20.59223
2014	23.5245
2015	21.96587
2016	19.88661
2017	26.73143