Year	Index
1991-01-01	60.5
1993-01-01	52.6
1996-01-01	48.3
1998-01-01	49.1
2002-01-01	42.1
2004-01-01	54.3
2006-01-01	54.6
2010-01-01	55.6
2015-01-01	57.1