62% (1994)

53% (1998)

61% (1995)

74% (1995)

66% (1992)

63% (1997)

67% (1988)

65% (1996)

68% (1997)

64% (1996)

75% (1991)

67% (1988)

63% (1996)

68% (1996)

61% (1999)

60% (1988)

80% (1997)

63% (1997)

56% (1990)

58% (1994)