54% (1985)

52% (1987)

40% (1990)

53% (1988)

36% (1989)

53% (1986)

54% (1981)

49% (1988)

54% (1980)

50% (1988)

65% (1987)

40% (1982)

47% (1986)

46% (1985)

48% (1988)

58% (1991)

44% (1994)

36% (1991)

43% (1987)

42% (1990)