62% (1980)

70% (1972)

58% (1995)

63% (1988)

61% (1986)

70% (1988)

47% (1995)

72% (1968)

73% (1982)

72% (1976)

60% (1996)

54% (1988)

58% (1982)

70% (1979)

52% (1975)

59% (1980)

60% (1986)

57% (1979)

38% (1985)

50% (1986)