Year	Percent
1991-01-01	43.7330017089844
1992-01-01	43.2630004882813
1993-01-01	43.1220016479492
1994-01-01	44.2709999084473
1995-01-01	41.5929985046387
1996-01-01	44.4389991760254
1997-01-01	43.8800010681152
1998-01-01	43.9630012512207
1999-01-01	44.1679992675781
2000-01-01	44.8419990539551
2001-01-01	43.8590011596680
2002-01-01	44.0489997863770
2003-01-01	46.8209991455078
2004-01-01	45.2729988098145
2005-01-01	46.8079986572266
2006-01-01	45.8559989929199
2007-01-01	45.8919982910156
2008-01-01	45.2080001831055
2009-01-01	44.1069984436035
2010-01-01	45.3320007324219
2011-01-01	38.4039993286133
2012-01-01	45.1189994812012
2013-01-01	44.8540000915527
2014-01-01	44.6100006103516
2015-01-01	44.5740013122559
2016-01-01	45.7070007324219
2017-01-01	45.9449996948242