Year	Percent
1999-01-01	22.8724
2000-01-01	25.3970
2001-01-01	15.4046
2002-01-01	12.2501
2003-01-01	18.5072
2004-01-01	22.4769
2005-01-01	29.1261
2006-01-01	26.3271
2007-01-01	33.3898
2008-01-01	20.8308
2009-01-01	33.0975
2010-01-01	30.5105
2011-01-01	22.1931
2012-01-01	22.3968
2013-01-01	25.1166
2014-01-01	29.6944
2015-01-01	34.3755
2016-01-01	26.0978