Year	% (cumulative)
1977	4.59999990463257
1992	6.93040990829468
2002	12.6461095809937
2006	14.6027555465698
2007	14.6735095977783
2008	15.2645196914673
2009	15.540060043335
2010	15.9055700302124
2011	16.6837596893311
2012	17.0980491638184
2013	17.3730602264404
2014	17.2269802093506
2015	17.7632293701172
2016	17.7419300079346
2017	17.7385807037354
2018	17.9597644805908
2019	18.3722896575928
2020	18.6828002929688
2021	18.756160736084
2022	19.5579700469971