Year	Percent
1998	11.20263
1999	10.76529
2000	10.79661
2001	11.39087
2002	11.77447
2003	12.83362
2004	13.58714
2005	13.93953
2006	14.25436
2007	15.27457
2008	18.05081
2009	19.94422
2010	19.2353
2011	18.60314
2012	18.78222
2013	16.78877
2014	15.32677