60% (2005)

60% (1996)

54% (1993)

81% (1980)

72% (1997)

68% (1995)

51% (2005)

59% (1997)

62% (2001)

61% (2002)

59% (1999)

47% (2002)

59% (1994)

47% (1998)

59% (1995)

60% (1998)

52% (2006)

63% (1996)

65% (2004)

54% (1996)