Year Number 1996 -1.13137912750244 1998 -1.73167061805725 2000 -1.99520063400269 2002 -1.58324420452118 2003 -2.09539484977722 2004 -1.90860557556152 2005 -1.5181759595871 2006 -1.41766691207886 2007 -1.19806575775146 2008 -1.05679154396057 2009 -0.751153647899628 2010 -0.853916168212891 2011 -0.770114183425903 2012 -0.593262791633606 2013 -0.51926463842392 2014 -0.416824042797089 2015 -0.619956314563751 2016 -0.379699736833572 2017 -0.504938900470734 2018 -0.552077412605286 2019 -0.502156674861908 2020 -0.462322682142258 2021 -0.531467199325562 2022 -0.439423859119415