Year	Number
2004-01-01	2.6776
2005-01-01	2.6283
2006-01-01	2.4622
2007-01-01	2.4070
2008-01-01	2.3438
2009-01-01	2.2925
2010-01-01	2.2330
2011-01-01	2.1964
2012-01-01	2.2529