Year	Number
2006-01-01	18496868.0
2007-01-01	19175202.0
2008-01-01	20061898.0
2009-01-01	19983148.0
2010-01-01	19972523.0
2011-01-01	20157337.0
2012-01-01	21517245.0
2013-01-01	23353837.9
2014-01-01	25861023.0
2015-01-01	26953411.3