Year	Percent
1991-01-01	18.44000053405760
1992-01-01	18.46899986267090
1993-01-01	16.61000061035160
1994-01-01	17.44899940490720
1995-01-01	10.73999977111820
1996-01-01	13.15900039672850
1997-01-01	15.23200035095210
1998-01-01	11.74899959564210
1999-01-01	9.41100025177002
2000-01-01	9.23799991607666
2001-01-01	9.26799964904785
2002-01-01	11.74300003051760
2003-01-01	13.81599998474120
2004-01-01	7.36399984359741
2005-01-01	6.78100013732910
2006-01-01	6.61100006103516
2007-01-01	14.96300029754640
2008-01-01	9.61299991607666
2009-01-01	9.97700023651123
2010-01-01	14.35900020599370
2011-01-01	10.14999961853030
2012-01-01	8.23600006103516
2013-01-01	10.47500038146970
2014-01-01	11.85000038146970
2015-01-01	12.57199954986570
2016-01-01	19.85799980163570
2017-01-01	18.88199996948240