Year	Percent
1997-01-01	97.01
1998-01-01	104.39
1999-01-01	113.16
2000-01-01	107.48
2001-01-01	99.57
2002-01-01	89.53
2003-01-01	98.04
2004-01-01	105.56
2005-01-01	117.36
2006-01-01	128.86
2007-01-01	117.07
2008-01-01	94.60
2009-01-01	112.29
2010-01-01	122.62
2011-01-01	129.30
2012-01-01	146.87
2013-01-01	150.66
2014-01-01	175.59
2015-01-01	172.05
2016-01-01	183.71