69% (1981)

50% (1983)

63% (1984)

57% (1978)

50% (1981)

70% (1989)

53% (1980)

69% (1984)

56% (1996)

57% (1995)

57% (1990)

45% (1992)

52% (1986)

52% (1980)

50% (1994)

65% (1991)

42% (1995)

50% (1984)

54% (1980)

58% (1998)