Year	Number
2004-01-01	2.7166
2005-01-01	3.8713
2006-01-01	5.4953
2007-01-01	7.3326
2008-01-01	8.8107
2009-01-01	8.2693
2010-01-01	7.8053
2011-01-01	6.7833
2012-01-01	7.2311
2013-01-01	1.5599
2014-01-01	1.6861
2015-01-01	1.6424
2016-01-01	1.4331
2017-01-01	1.2221