Year	% (cumulative)
1970	12.8930501937866
1980	18.6215705871582
1990	26.9245300292969
2000	34.7364883422852
2005	38.8800315856934
2006	36.8537101745605
2007	36.3116416931152
2008	38.7043609619141
2011	39.1928787231445
2017	43.5241889953613