Year	Percent
1999-01-01	34.9626299826690
2000-01-01	34.7701460248783
2001-01-01	35.2200691543005
2002-01-01	34.9427315948711
2003-01-01	35.5654601116514
2004-01-01	35.2775482472764
2005-01-01	35.4905217391602
2006-01-01	36.4304258464645
2007-01-01	37.3293996517472
2008-01-01	38.5565196967276
2009-01-01	37.3900171679534
2010-01-01	37.0679054180347
2011-01-01	36.9719582264301
2012-01-01	36.9860419822549
2013-01-01	37.2608021910700