70% (1981)

63% (1981)

62% (1982)

42% (1983)

55% (1980)

52% (1988)

53% (1989)

52% (1979)

58% (1979)

51% (1987)

57% (1990)

43% (1992)

26% (1993)

50% (1990)

42% (1989)

52% (1990)

44% (1987)

48% (1988)

50% (1982)

48% (1983)