54% (1995)

61% (1994)

56% (2001)

59% (1986)

63% (1993)

57% (1991)

55% (2000)

62% (2008)

58% (1996)

67% (1986)

53% (1998)

54% (2010)

54% (1994)

53% (1987)

64% (1999)

55% (1994)

52% (1991)

66% (1994)

66% (1988)

57% (2008)