68% (1992)

56% (1996)

46% (1998)

67% (1988)

61% (1997)

62% (1991)

47% (1995)

62% (1990)

72% (1996)

44% (1995)

52% (1989)

41% (1989)

24% (1991)

43% (1990)

64% (1990)

45% (1988)

50% (1996)

55% (1994)

55% (1993)

25% (1996)