65% (1984)

56% (1976)

50% (1988)

60% (1985)

50% (1974)

48% (1981)

60% (1987)

51% (1981)

55% (1979)

54% (1983)

64% (1977)

53% (1984)

56% (1977)

57% (1981)

30% (1987)

63% (1982)

30% (1980)

50% (1975)

50% (1986)

58% (1987)