Year	Percent
1991-01-01	43.4220008850098
1992-01-01	43.4640007019043
1993-01-01	43.8050003051758
1994-01-01	43.9739990234375
1995-01-01	44.2309989929199
1996-01-01	44.4860000610352
1997-01-01	44.2560005187988
1998-01-01	44.0660018920898
1999-01-01	43.7890014648438
2000-01-01	43.6430015563965
2001-01-01	43.4729995727539
2002-01-01	43.2540016174316
2003-01-01	43.0839996337891
2004-01-01	42.8759994506836
2005-01-01	42.6640014648438
2006-01-01	42.4379997253418
2007-01-01	42.1520004272461
2008-01-01	41.8209991455078
2009-01-01	41.4269981384277
2010-01-01	41.3959999084473
2011-01-01	41.1629981994629
2012-01-01	40.9809989929199
2013-01-01	40.9339981079102
2014-01-01	40.8400001525879
2015-01-01	40.7239990234375
2016-01-01	40.6510009765625
2017-01-01	40.5649986267090