Year	Percent
1991-01-01	5.92500019073486
1992-01-01	5.48199987411499
1993-01-01	5.28499984741211
1994-01-01	4.97300004959106
1995-01-01	4.61100006103516
1996-01-01	4.39900016784668
1997-01-01	4.01300001144409
1998-01-01	3.67000007629395
1999-01-01	3.50900006294250
2000-01-01	2.62500000000000
2001-01-01	2.40799999237061
2002-01-01	5.81500005722046
2003-01-01	6.33500003814697
2004-01-01	5.85300016403198
2005-01-01	4.61899995803833
2006-01-01	3.41700005531311
2007-01-01	4.72599983215332
2008-01-01	5.33799982070923
2009-01-01	5.94799995422363
2010-01-01	5.72800016403198
2011-01-01	7.49800014495850
2012-01-01	4.78000020980835
2013-01-01	5.91300010681152
2014-01-01	6.11000013351440
2015-01-01	5.88700008392334
2016-01-01	6.01999998092651
2017-01-01	5.80000019073486