78% (1964)

70% (2007)

72% (1992)

70% (2009)

65% (1985)

67% (1997)

80% (1968)

75% (1972)

0% (1990)

65% (2003)

65% (1983)

70% (1987)

71% (1986)

62% (2004)

65% (1956)

64% (2003)

64% (1982)

60% (1963)

70% (1989)

66% (1989)