Year	Percent
1998	10.8147
2002	19.81828
2003	19.68689
2004	21.37206
2005	22.0079
2006	22.87955
2007	21.77817
2008	22.70049
2009	23.74239
2010	24.09019
2011	23.31435
2012	23.34109
2013	21.70667
2014	21.79805