57% (1990)

49% (1987)

51% (1987)

48% (1986)

58% (1986)

49% (1990)

51% (1988)

53% (1988)

36% (1991)

45% (1985)

44% (1989)

30% (1989)

43% (1995)

52% (1992)

34% (1986)

40% (1994)

47% (1993)

39% (1991)

39% (1990)

43% (1985)