Year	% (cumulative)
1970	12.05774974823
1980	18.4519500732422
1990	28.6630897521973
2000	37.6096115112305
2005	42.2522888183594
2006	40.8999214172363
2007	40.6750793457031
2008	42.7990989685059
2011	43.8829917907715
2017	50.0497093200684