53% (1987)

61% (1985)

58% (1993)

57% (1991)

65% (1983)

67% (1981)

46% (1991)

58% (1986)

67% (1980)

61% (1988)

56% (1983)

55% (1987)

60% (1990)

58% (1990)

58% (1985)

44% (1988)

57% (1987)

59% (1989)

61% (1993)

69% (1988)