Year	Percent
1991-01-01	33.628000000000000
1992-01-01	20.027700000000000
1993-01-01	23.401600000000000
1994-01-01	27.538900000000000
1995-01-01	27.417700000000000
1996-01-01	30.600300000000000
1997-01-01	33.259700000000000
1998-01-01	36.599900000000000
1999-01-01	37.638500000000000
2000-01-01	40.303100000000000
2001-01-01	45.545500000000000
2002-01-01	49.513100000000000
2003-01-01	49.714600000000000
2004-01-01	49.787700000000000
2005-01-01	45.594100000000000
2006-01-01	46.018400000000000
2007-01-01	45.681900000000000
2008-01-01	47.023700000000000
2009-01-01	50.494100000000000
2010-01-01	51.367600000000000
2011-01-01	51.888000000000005
2012-01-01	53.442100000000000
2013-01-01	52.621600000000000
2014-01-01	52.183200000000000
2015-01-01	53.429300000000000
2016-01-01	54.593000000000000