Year days 2003 634.8461538461538 2004 642.6875 2005 638 2006 638 2007 634.45 2008 632.95 2009 627.95 2010 624.95 2011 624.95 2012 633.3809523809524 2013 633.3809523809524 2014 630.5238095238095 2015 626.6818181818181 2016 624.4090909090909 2017 622.2727272727273 2018 622.2727272727273 2019 622.2727272727273