Year	Number
2004-01-01	0.1319
2005-01-01	0.1385
2006-01-01	0.1516
2007-01-01	0.1762
2008-01-01	0.1746
2009-01-01	0.2024
2010-01-01	0.2368
2011-01-01	0.2836
2012-01-01	0.3295
2013-01-01	0.3549
2014-01-01	0.4073
2015-01-01	0.4507
2016-01-01	0.4671