Year % (cumulative) 1973 16.4445209503174 2001 36.3465003967285 2002 37.5999984741211 2003 38.8300018310547 2004 38.8800010681152 2005 39.9300003051758 2006 40.5999984741211 2007 41.4099998474121 2008 42.5299987792969 2009 42.8300018310547 2010 42.0299987792969 2011 43.2799987792969 2012 44.189998626709 2013 44.9000015258789 2014 46.5900001525879 2015 45.4799995422363 2016 45.4199981689453 2017 46.5299987792969 2018 47.189998626709 2019 48.0999984741211 2020 48.189998626709 2021 50.189998626709 2022 51.2799987792969