Year	Number
2004-01-01	24.3293
2005-01-01	24.3127
2006-01-01	24.1182
2007-01-01	23.9253
2008-01-01	23.7339
2009-01-01	23.5440
2010-01-01	23.3557
2011-01-01	23.1559
2012-01-01	22.8999
2013-01-01	21.7853
2014-01-01	20.2757
2015-01-01	20.3527
2016-01-01	19.9711