72% (1980)

67% (1994)

63% (1980)

77% (1979)

70% (1979)

63% (1981)

65% (1995)

78% (1969)

72% (1994)

68% (1978)

70% (1977)

64% (2006)

66% (1982)

61% (1977)

69% (1976)

64% (2000)

40% (1989)

60% (1984)

69% (1982)

70% (1996)