Year Number 1996 2.12765955924988 1998 3.72340416908264 2000 0.52910053730011 2002 0 2003 4.52261304855347 2004 4.36893224716187 2005 0.970873773097992 2006 0.483091801404953 2007 0.483091801404953 2008 0.961538434028625 2009 1.42180097103119 2010 1.42180097103119 2011 1.89573454856873 2012 1.89573454856873 2013 1.89573454856873 2014 4.2857141494751 2015 0.952380955219269 2016 2.38095235824585 2017 3.80952382087708 2018 3.30188679695129 2019 2.8301887512207 2020 2.35849046707153 2021 3.30188679695129 2022 2.35849046707153