Year	Percent
1998	28.92871
1999	29.29272
2000	27.16046
2001	27.05851
2002	27.00313
2003	27.87828
2004	26.59278
2005	25.39476
2006	25.70922
2007	25.40733
2008	26.29943
2009	29.28391
2010	28.43686
2011	29.42218
2012	26.82327
2013	27.43328
2014	26.93832