Year	% (cumulative)
1970	25
1975	32.7000007629395
1980	42.0348701477051
1985	49.6456909179688
1988	46.5704498291016
2005	51.0290603637695
2006	51.8809013366699
2007	52.9619407653809
2008	55.5279197692871
2012	64.48291015625
2013	57.7499809265137
2015	62.1568489074707
2017	61.9986686706543
2018	61.7958297729492