63% (1993)

56% (1996)

61% (1999)

62% (1995)

65% (1987)

62% (1998)

64% (2003)

56% (2004)

53% (1988)

56% (1995)

57% (1989)

54% (2002)

58% (1993)

66% (2006)

58% (2011)

43% (1995)

56% (1987)

54% (2003)

62% (1988)

69% (2005)