Year	Percent
1999-01-01	48.7830178819838
2000-01-01	50.2463077042367
2001-01-01	51.2001125379011
2002-01-01	51.4584775474734
2003-01-01	51.9631166767162
2004-01-01	52.3819711900598
2005-01-01	53.6825623852546
2006-01-01	54.2839355300935
2007-01-01	54.3615299780288
2008-01-01	52.2981464435355
2009-01-01	47.1813134046298
2010-01-01	45.6801442628700
2011-01-01	44.3816309754660
2012-01-01	42.0423099746398
2013-01-01	40.9877583804157
2014-01-01	41.7297502862128