75% (1994)

63% (1995)

71% (1993)

69% (2006)

68% (1998)

58% (1991)

61% (2002)

63% (1997)

56% (1992)

65% (1999)

60% (1986)

65% (2005)

63% (2010)

58% (2004)

68% (2006)

57% (1997)

65% (1987)

60% (2003)

63% (1990)

61% (1994)