Year	Percent
1991	5.70794
1992	10.48362
1993	8.64248
1994	14.21297
1995	15.75504
1996	8.33553
1997	22.39175
1998	26.8045
1999	27.6788
2000	29.20569
2001	32.33874
2002	39.35873
2003	47.86709
2004	56.17906
2005	46.99259
2006	41.97481
2007	40.03555
2008	33.78941
2009	33.27112
2010	34.01462
2011	36.13554
2012	39.97548
2013	38.62848
2014	41.86433
2015	55.22343
2016	63.48482