79% (1990)

71% (2010)

66% (1996)

70% (1988)

45% (1993)

73% (1989)

66% (2000)

63% (1994)

72% (2004)

71% (1993)

66% (1989)

64% (1990)

56% (1999)

66% (2006)

57% (1996)

66% (1997)

92% (1991)