73% (1976)

65% (1995)

49% (1995)

49% (2004)

44% (2001)

65% (1999)

58% (2000)

61% (1998)

45% (2002)

52% (1988)

61% (1997)

49% (2003)

59% (1990)

56% (1993)

58% (1993)

49% (1986)

55% (1989)

62% (1996)

61% (1999)

56% (1996)