68% (1986)

60% (1988)

60% (2008)

60% (1986)

64% (1991)

35% (2006)

65% (1981)

68% (1988)

62% (1992)

67% (1999)

68% (1983)

58% (1997)

57% (1990)

55% (1986)

75% (1983)

45% (1993)

20% (1985)

43% (1957)

53% (1992)

80% (1981)