73% (1976)

45% (2002)

43% (2001)

65% (1995)

50% (2004)

59% (1990)

61% (1998)

58% (1993)

59% (2000)

61% (1997)

50% (1986)

56% (1996)

62% (1999)

53% (1992)

65% (1999)

56% (1993)

50% (1990)

62% (1996)

55% (1989)

49% (1995)