Year	% (cumulative)
1972	9.02184009552002
1981	18.4954395294189
2000	37.2200012207031
2001	38.0499992370605
2002	39.1199989318848
2003	38.6800003051758
2004	40.689998626709
2005	41.3800010681152
2006	42.3699989318848
2007	44.439998626709
2008	44.6399993896484
2009	45.0400009155273
2010	44.9099998474121
2011	45.2900009155273
2012	47.4799995422363
2013	46.4599990844727
2014	46.7099990844727
2015	47.9799995422363
2016	47.8600006103516
2017	48.7599983215332
2018	49.0200004577637
2019	50.2799987792969
2020	50.0999984741211
2021	49.8699989318848
2022	51.6199989318848