54% (1983)

55% (1987)

69% (1986)

54% (1991)

56% (1977)

31% (1997)

58% (1992)

57% (1980)

73% (1989)

50% (1982)

54% (1990)

74% (1992)

40% (1987)

42% (1980)

69% (1981)

72% (1993)

38% (1991)

38% (1981)

60% (1995)

47% (1982)