Year	Percent
1986-01-01	45.3691115116707
1987-01-01	45.1582825721804
1988-01-01	45.8183751819819
1989-01-01	47.0205373628804
1990-01-01	46.0374438696199
1991-01-01	45.7156135723057
1992-01-01	45.9904602634838
1993-01-01	46.0897212164971
1994-01-01	44.9556705299239
1995-01-01	44.1850718263510
1996-01-01	42.8378633906720
1997-01-01	42.9201672750089
1998-01-01	43.0307434635687
1999-01-01	42.7183960896443
2000-01-01	42.5912538996282
2001-01-01	41.7391305886056
2002-01-01	41.0133779460808
2003-01-01	40.7025956671511
2004-01-01	40.2179645743300
2005-01-01	39.2095898969532
2006-01-01	38.7058047093961
2007-01-01	38.3150524240109
2008-01-01	38.0322254786627
2009-01-01	38.1114126397504
2010-01-01	38.3591961559200
2011-01-01	37.9185880500001
2012-01-01	37.8770290801090
2013-01-01	37.4962561634908
2014-01-01	36.6076577927872
2015-01-01	36.6343413221675
2016-01-01	35.4772605971178
2017-01-01	34.6241745746800