71% (2000)

30% (1999)

31% (1999)

65% (1996)

50% (2001)

42% (2000)

43% (1999)

54% (1998)

51% (1997)

40% (2000)

70% (1987)

60% (1996)

44% (1995)

40% (1998)

55% (2000)

43% (2000)

30% (1990)

57% (2000)

57% (1998)

52% (2001)