Year	% (cumulative)
1970	99.4000015258789
1975	97.9890975952148
1980	97.9062118530273
1990	99.7955703735352
2006	99.6601486206055
2007	100
2008	100
2009	100
2010	100
2011	100
2012	99.9230270385742
2013	99.9468841552734
2014	99.7288665771484
2015	99.7387084960938
2016	99.7464828491211
2017	99.7580718994141
2018	99.5888061523438
2019	99.7835311889648
2020	99.2197952270508
2021	96.0919799804688
2022	98.955192565918