Year	Percent
2000-01-01	24.7544413619008
2001-01-01	24.6657427781459
2002-01-01	24.2855646301919
2003-01-01	24.5230322407388
2004-01-01	24.0176142700070
2005-01-01	23.9388254596587
2006-01-01	23.5876740568478
2007-01-01	23.5197732799496
2008-01-01	23.4162655610514
2009-01-01	24.0321699978991
2010-01-01	23.5670299558307
2011-01-01	23.1593562563471
2012-01-01	22.9960426727463
2013-01-01	22.6951158095892
2014-01-01	21.6757152414809
2015-01-01	21.4659488974108
2016-01-01	21.1695305300398
2017-01-01	20.8894681291678