Year	Index
1981-01-01	43.6
1989-01-01	42.4
2006-01-01	45.9
2007-01-01	46.4
2008-01-01	45.1
2009-01-01	45.6
2010-01-01	44.5
2011-01-01	42.2
2012-01-01	39.9
2013-01-01	40.5
2014-01-01	40.1
2015-01-01	40.2
2016-01-01	39.7