Year	Number
2004-01-01	19.5803
2005-01-01	18.9970
2006-01-01	19.1110
2007-01-01	20.7678
2008-01-01	20.2198
2009-01-01	19.7024
2010-01-01	20.5439
2011-01-01	20.6925
2012-01-01	22.0384
2013-01-01	22.0066
2014-01-01	22.6088
2015-01-01	21.4358