Year	Percent
1999-01-01	3.31910662848784
2000-01-01	3.08701032110846
2001-01-01	2.98871891608188
2002-01-01	2.97385939988302
2003-01-01	3.04954764160640
2004-01-01	3.08312813012800
2005-01-01	3.21574951496285
2006-01-01	3.31384858188883
2007-01-01	2.69578087723355
2008-01-01	2.23902454994000
2009-01-01	2.69521128761342
2010-01-01	3.23101989026939
2011-01-01	3.69553890187374
2012-01-01	4.21640354254910
2013-01-01	4.84295944913371
2014-01-01	4.73466641030571