Year Number 2008 1.01208281517029 2009 0.430509388446808 2010 -1.04482114315033 2011 -1.04214704036713 2012 -1.0385023355484 2013 -0.966146647930145 2014 -0.340774536132813 2015 -0.200406447052956 2016 -0.285933345556259 2017 -0.244493424892426 2018 -0.675402104854584 2019 -0.348640084266663 2020 -0.279240250587463 2021 -0.113625250756741 2022 -0.252448588609695