55% (1988)

40% (1990)

53% (1985)

53% (1987)

65% (1987)

51% (1986)

55% (1981)

50% (1986)

54% (1980)

49% (1988)

50% (1988)

40% (1982)

37% (1989)

51% (1985)

52% (1986)

35% (1988)

47% (1986)

43% (1990)

45% (1987)

44% (1994)