68% (1989)

70% (1985)

67% (1981)

54% (1991)

58% (1989)

65% (1984)

49% (1994)

48% (1995)

63% (1986)

50% (1992)

63% (1989)

47% (1987)

62% (1988)

54% (1995)

57% (1986)

60% (1987)

47% (1979)

60% (1980)

55% (1987)

64% (1986)