69% (1987)

60% (1997)

53% (2003)

66% (1998)

58% (2007)

69% (2000)

53% (1991)

58% (2005)

56% (1998)

57% (1992)

49% (1991)

60% (1998)

63% (1999)

42% (2004)

66% (1986)

60% (1999)

59% (1999)

49% (1997)

60% (1999)

63% (1992)