50% (1993)

40% (2001)

20% (1983)

20% (1998)

0% (1989)

20% (1984)

65% (1999)

20% (1990)

40% (1996)

40% (1986)

0% (2000)

37% (1998)

30% (1988)

0% (1986)

20% (1991)

20% (1984)

45% (1984)

20% (1990)

20% (1984)

35% (1988)