38% (1992)

32% (1990)

46% (1988)

28% (1989)

30% (1992)

29% (1990)

40% (1990)

20% (1991)

33% (1989)

22% (1989)

50% (1991)

42% (1992)

43% (1993)

38% (1989)

40% (1992)

40% (1988)

43% (1991)

38% (1989)