50% (1978)

58% (1981)

66% (1993)

64% (1989)

59% (1974)

60% (1982)

56% (1977)

62% (1971)

50% (1977)

60% (1981)

61% (1985)

55% (1979)

50% (1980)

51% (1981)

54% (1983)

66% (1991)

70% (1988)

0% (1992)

50% (1975)

58% (1988)