Year Number 1996 0.361694604158401 1998 1.0588550567627 2000 1.15730142593384 2002 0.831208944320679 2003 1.18648135662079 2004 1.12390494346619 2005 1.0276792049408 2006 0.926921546459198 2007 0.952527701854706 2008 1.11487662792206 2009 1.22328507900238 2010 1.15385591983795 2011 1.17473101615906 2012 1.22359883785248 2013 1.21254646778107 2014 0.977457761764526 2015 0.983597457408905 2016 0.884123742580414 2017 0.647981882095337 2018 0.649283885955811 2019 0.68427562713623 2020 0.66954380273819 2021 0.833261430263519 2022 0.958558142185211