35% (1976)

61% (1979)

59% (1969)

80% (1981)

68% (1970)

68% (1982)

66% (1970)

58% (1979)

60% (1988)

50% (1965)

58% (1990)

60% (1985)

0% (1988)

51% (1973)

60% (1981)

20% (1972)

0% (1991)

60% (1980)

62% (1976)

60% (1958)