Year	Percent
2000-01-01	4.31358550394499
2001-01-01	3.88703932507889
2002-01-01	3.17392529346321
2003-01-01	3.21007551621374
2004-01-01	3.32719680034153
2005-01-01	3.49607174909088
2006-01-01	3.42537299501229
2007-01-01	3.29806661465864
2008-01-01	3.21217616443863
2009-01-01	3.75974148191457
2010-01-01	3.68415272944856
2011-01-01	3.24645504562927
2012-01-01	3.09205611107926
2013-01-01	2.98769606600486
2014-01-01	3.14699803672864
2015-01-01	3.24157704227712
2016-01-01	3.38845718224555
2017-01-01	3.43499715740080