Year	Percent
1999	25.98478
2000	26.81863
2001	27.70005
2002	30.47864
2003	33.89037
2004	31.21651
2005	31.94663
2006	31.68213
2007	32.3864
2008	34.58503
2009	37.33226
2010	36.87532
2011	37.82274
2013	37.92279
2014	39.1193