67% (1984)

65% (1995)

65% (1999)

65% (1994)

60% (1999)

63% (1992)

64% (1987)

59% (1990)

65% (1991)

64% (1990)

70% (1982)

62% (1990)

56% (1990)

52% (1989)

30% (1980)

55% (1990)

0% (1989)