Year	Percent
1999	26.39854
2000	27.45393
2001	28.86026
2002	28.96929
2003	29.5211
2004	32.70983
2005	32.41884
2006	31.53999
2007	30.14913
2008	30.21151
2009	37.1795
2010	34.8872
2011	32.56221
2012	31.63513
2013	30.33821
2014	29.31617