Year	Percent
1971	59.14829
1972	57.24728
1973	61.40239
1974	62.48495
1975	73.99054
1976	73.52269
1977	91.09473
1978	89.27442
1980	92.16087
1983	64.41482
1985	71.37461
1986	70.49337
1987	62.5936
1988	63.55022
1989	64.44782
1993	64.41775
1999	62.56158
2000	61.29025
2004	90.55843
2007	76.1168