73% (1989)

77% (1991)

73% (1976)

58% (1980)

65% (1983)

58% (1979)

67% (1977)

69% (1990)

68% (1981)

61% (1977)

72% (1983)

53% (1986)

60% (1996)

75% (1981)

48% (1998)

68% (1988)

40% (1980)

0% (1997)

79% (1979)

69% (1985)