68% (1990)

71% (1987)

67% (1993)

74% (1987)

67% (1995)

64% (2001)

61% (2007)

57% (2004)

53% (1999)

40% (2005)

50% (1998)

65% (2009)

60% (2005)

55% (1993)

60% (1998)

0% (1996)