50% (2003)

48% (1992)

45% (1993)

38% (1995)

33% (1989)

56% (1988)

35% (1987)

69% (2006)

54% (1990)

30% (2008)

51% (1995)

46% (2004)

46% (2006)

39% (1987)

47% (2007)

49% (1995)

38% (1990)

55% (2005)

78% (2007)

34% (2004)