Year Number 2007-01-01 15121.8269 2008-01-01 20599.6213 2009-01-01 18862.8570 2010-01-01 15595.3669 2011-01-01 14923.3401 2012-01-01 15270.9715 2013-01-01 14239.9250 2014-01-01 14303.4436 2015-01-01 13264.9122 2016-01-01 11942.1654 2017-01-01 7969.7226