Year	Percent
1991-01-01	7.23899984359741
1992-01-01	7.76499986648560
1993-01-01	8.73999977111816
1994-01-01	9.68400001525879
1995-01-01	10.65499973297120
1996-01-01	11.60000038146970
1997-01-01	13.71199989318850
1998-01-01	15.83600044250490
1999-01-01	17.84199905395510
2000-01-01	18.11300086975100
2001-01-01	17.54199981689450
2002-01-01	19.72999954223630
2003-01-01	19.40299987792970
2004-01-01	21.51199913024900
2005-01-01	24.39399909973140
2006-01-01	23.61800003051760
2007-01-01	22.25600051879880
2008-01-01	19.02000045776370
2009-01-01	18.24799919128420
2010-01-01	16.87700080871580
2011-01-01	17.33300018310550
2012-01-01	14.96100044250490
2013-01-01	15.15900039672850
2014-01-01	15.18700027465820
2015-01-01	16.68899917602540
2016-01-01	14.91899967193600
2017-01-01	15.23700046539310