Year	Number
2004-01-01	17.6553
2005-01-01	19.2827
2006-01-01	18.1216
2007-01-01	19.4769
2008-01-01	22.0214
2009-01-01	24.3284
2010-01-01	29.4969
2011-01-01	28.7273
2012-01-01	30.9793