50% (1993)

59% (1977)

53% (1980)

68% (1978)

72% (1978)

66% (1975)

72% (1981)

60% (1980)

68% (1981)

58% (1978)

66% (1988)

59% (1976)

46% (1979)

50% (1981)

48% (1980)

59% (1984)

62% (1990)

70% (1983)

59% (1982)

68% (1978)