20% (1997)

20% (1990)

50% (2005)

58% (1990)

20% (1993)

20% (1981)

20% (1984)

0% (1968)

10% (1997)

50% (2001)

0% (1980)

0% (1982)

30% (2004)

20% (2005)

20% (1993)

20% (1982)

0% (1981)

20% (1987)

20% (1989)

50% (1980)