Year	Percent
1991-01-01	3.19000005722046
1992-01-01	4.51999998092651
1993-01-01	6.37400007247925
1994-01-01	5.97599983215332
1995-01-01	5.46000003814697
1996-01-01	4.95100021362305
1997-01-01	6.44600009918213
1998-01-01	6.06099987030029
1999-01-01	6.17000007629395
2000-01-01	5.00699996948242
2001-01-01	5.62500000000000
2002-01-01	5.57399988174438
2003-01-01	8.49899959564209
2004-01-01	7.71500015258789
2005-01-01	8.77000045776367
2006-01-01	7.68599987030029
2007-01-01	7.11499977111816
2008-01-01	7.00000000000000
2009-01-01	8.48299980163574
2010-01-01	8.22599983215332
2011-01-01	7.68900012969971
2012-01-01	8.30300045013428
2013-01-01	8.73600006103516
2014-01-01	8.59200000762939
2015-01-01	8.81499958038330
2016-01-01	8.57600021362305
2017-01-01	8.05500030517578