Year	%
1972	8.9791
1973	7.90051
1974	7.03323
1976	6.81069
1985	82.92931
1986	85.27594
1987	84.6134
1988	84.12937
1989	81.06215
1990	80.28486
1991	79.78983
2011	80.17439
2012	74.2635
2013	71.03562
2014	67.14811
2015	70.9663
2016	78.12549
2017	72.04403