Year	Percent
1991-01-01	4.46899986267090
1992-01-01	4.92600011825562
1993-01-01	5.44999980926514
1994-01-01	5.93200016021729
1995-01-01	6.39900016784668
1996-01-01	6.40100002288818
1997-01-01	7.18699979782104
1998-01-01	8.04199981689453
1999-01-01	8.82100009918213
2000-01-01	9.48900032043457
2001-01-01	8.62899971008301
2002-01-01	7.75899982452393
2003-01-01	6.61499977111816
2004-01-01	7.85400009155273
2005-01-01	8.80099964141846
2006-01-01	7.26700019836426
2007-01-01	8.43000030517578
2008-01-01	9.21199989318848
2009-01-01	10.94999980926510
2010-01-01	6.31699991226196
2011-01-01	7.26499986648560
2012-01-01	8.20699977874756
2013-01-01	10.01299953460690
2014-01-01	10.32600021362300
2015-01-01	10.65400028228760
2016-01-01	11.07900047302250
2017-01-01	11.36499977111820