71% (1985)

60% (2005)

67% (1978)

60% (1988)

69% (2002)

77% (1960)

63% (1955)

67% (1980)

65% (1958)

65% (1964)

62% (2003)

69% (1920)

46% (1993)

54% (1989)

65% (1976)

56% (1976)

72% (1963)

58% (1975)

62% (1966)

55% (1982)