68% (1993)

72% (1999)

75% (2008)

75% (1995)

65% (2002)

70% (2003)

71% (1993)

69% (1989)

69% (1990)

68% (2007)

72% (1982)

66% (1998)

64% (2005)

63% (1995)

72% (1985)

63% (2011)

65% (1999)

56% (1999)

59% (2014)

66% (1981)