Year	Percent
1998	12.81001
2001	17.45173
2002	17.70068
2003	26.42003
2004	16.1798
2005	22.31391
2006	21.09888
2007	17.3579
2008	23.05726
2009	23.90935
2010	14.31225
2011	14.96028
2012	15.472
2013	16.08169