72% (1976)

82% (1986)

60% (1976)

80% (1979)

65% (1982)

50% (1976)

70% (1986)

63% (1978)

50% (1989)

67% (1986)

78% (1976)

60% (1980)

50% (1981)

63% (1981)

80% (1982)

70% (1983)

63% (1973)

70% (1980)

50% (1988)

66% (1978)