61% (2009)

61% (2013)

71% (1986)

66% (1996)

70% (1984)

64% (1980)

65% (1995)

55% (1987)

71% (1981)

72% (1992)

64% (2002)

56% (1991)

72% (1989)

71% (1990)

70% (1999)

75% (2016)

68% (2003)

60% (1980)

61% (1997)

55% (1977)