Year Number 1996 7.65027332305908 1998 4.37158489227295 2000 4.37158489227295 2002 3.78378367424011 2003 4.32432413101196 2004 5.97014904022217 2005 12.7450981140137 2006 6.34146356582642 2007 9.22330093383789 2008 8.25242710113525 2009 7.17703342437744 2010 6.69856452941895 2011 8.53080558776855 2012 9.47867298126221 2013 10.9004735946655 2014 8.65384578704834 2015 7.14285707473755 2016 10 2017 10.9523811340332 2018 16.1904754638672 2019 15.2380952835083 2020 16.1904754638672 2021 12.380952835083 2022 12.7358493804932