Year Number 1996 6.38297891616821 1998 12.7659578323364 2000 8.99470901489258 2002 3.70370364189148 2003 4.52261304855347 2004 4.36893224716187 2005 0.970873773097992 2006 1.44927537441254 2007 2.4154589176178 2008 1.92307686805725 2009 2.84360194206238 2010 3.3175356388092 2011 3.79146909713745 2012 4.7393364906311 2013 4.7393364906311 2014 7.14285707473755 2015 6.66666650772095 2016 5.7142858505249 2017 3.80952382087708 2018 6.60377359390259 2019 6.13207530975342 2020 3.77358484268188 2021 0.943396210670471 2022 2.35849046707153