Year Number 1996 -0.9305459856987 1998 -0.903203785419464 2000 -0.906757354736328 2002 -0.717909097671509 2003 -0.777412176132202 2004 -0.757493495941162 2005 -0.772508382797241 2006 -0.650104701519012 2007 -0.632185876369476 2008 -0.666399776935577 2009 -0.704722344875336 2010 -0.694108724594116 2011 -0.667876601219177 2012 -0.608586847782135 2013 -0.501512408256531 2014 -0.44789931178093 2015 -0.476131945848465 2016 -0.442177504301071 2017 -0.582520842552185 2018 -0.504966139793396 2019 -0.435477554798126 2020 -0.390404462814331 2021 -0.422970861196518 2022 -0.44087877869606