37% (1976)

47% (1999)

55% (2006)

62% (1994)

57% (1978)

47% (1996)

60% (1994)

65% (2001)

80% (1969)

45% (1978)

49% (1995)

40% (2002)

42% (1987)

60% (1996)

45% (2002)

53% (1990)

65% (1973)

47% (1974)

66% (1990)

50% (1976)