Year	% (cumulative)
1970	21.010009765625
1975	26.603099822998
1980	36.5671005249023
1985	42.1321105957031
2005	42.2339782714844
2006	42.9274101257324
2007	44.7566604614258
2008	46.5866394042969
2012	56.2619094848633
2013	48.0933418273926
2015	54.445369720459
2017	54.2915382385254
2018	53.8853912353516