68% (1986)

68% (1988)

66% (1999)

75% (1983)

64% (1991)

64% (1981)

60% (2008)

62% (1992)

57% (1990)

72% (1996)

80% (1981)

47% (1993)

68% (1983)

58% (1997)

45% (1993)

35% (2006)

42% (1957)

48% (1983)

60% (1988)

53% (1992)