Year	Percent
1998	11.00509
1999	12.4855
2000	12.36096
2001	13.80273
2002	10.76551
2003	10.4994
2004	9.88178
2005	10.42185
2006	11.5965
2007	12.71181
2008	13.73516
2009	14.80218
2010	13.68812
2011	14.23689
2012	14.62254
2013	14.43766
2014	14.46554
2015	15.97743