Year	Percent
2000-01-01	24.6327676428471
2001-01-01	24.4561702039530
2002-01-01	25.8541310728353
2003-01-01	25.1493524683595
2004-01-01	25.7783290292123
2005-01-01	24.0042611148699
2006-01-01	22.2775733269569
2007-01-01	21.3007967217636
2008-01-01	18.6695165339471
2009-01-01	17.7680388351279
2010-01-01	17.7333718322950
2011-01-01	18.4615487767514
2012-01-01	19.7880011792277
2013-01-01	20.0685083345608
2014-01-01	21.6738683881390
2015-01-01	22.8220673565859
2016-01-01	22.9531044612938
2017-01-01	23.1315713309713