Year	Number
2004-01-01	7.4174
2005-01-01	6.8604
2006-01-01	6.5500
2007-01-01	6.5683
2008-01-01	6.6322
2009-01-01	6.7144
2010-01-01	6.7539
2011-01-01	7.1313
2012-01-01	7.2318
2013-01-01	7.2653
2014-01-01	7.3109
2015-01-01	7.3779
2016-01-01	8.2179
