Year	Number
2004-01-01	5.3322
2005-01-01	5.7903
2006-01-01	6.1093
2007-01-01	6.3541
2008-01-01	6.6172
2009-01-01	6.6638
2010-01-01	6.8149
2011-01-01	6.5541
2012-01-01	6.4991
2013-01-01	7.1480
2014-01-01	7.2570
2015-01-01	7.3055
2016-01-01	7.4770
2017-01-01	7.7229