57% (2000)

54% (1999)

50% (1996)

53% (1998)

46% (1997)

53% (1997)

56% (1987)

67% (1986)

45% (1996)

57% (1998)

60% (1987)

100% (1989)

90% (1995)

50% (1983)

42% (1996)