61% (2003)

65% (2009)

64% (1980)

59% (1982)

55% (1988)

62% (1986)

46% (1993)

62% (1984)

53% (1985)

60% (1972)

49% (2001)

55% (1987)

54% (1989)

47% (1992)

49% (1987)

80% (1978)