56% (1996)

66% (1995)

60% (1989)

54% (1993)

58% (1998)

62% (1998)

61% (1994)

65% (1995)

60% (1996)

54% (1995)

68% (1994)

56% (1995)

62% (1997)

55% (1998)

62% (1997)

54% (1996)

42% (1998)

58% (1997)

45% (1993)

67% (1993)