Year	Number
2008-01-01	6.8275
2009-01-01	6.9823
2010-01-01	6.9597
2011-01-01	7.7692
2012-01-01	6.9113
2013-01-01	8.2046
2014-01-01	8.7206
2015-01-01	8.6368
2016-01-01	8.9077
2017-01-01	8.0917