73% (1976)

65% (1995)

44% (2002)

59% (1990)

58% (1993)

65% (1999)

43% (2001)

49% (2004)

61% (1997)

60% (1998)

51% (2002)

58% (2000)

52% (1992)

68% (1990)

50% (1990)

45% (1995)

59% (1987)

61% (1999)

54% (1989)

52% (1988)