30% (1987)

45% (1992)

40% (1998)

47% (2005)

37% (2001)

58% (1990)

20% (1981)

0% (1981)

40% (2012)

35% (2001)

0% (1975)

20% (1999)

0% (1986)

0% (1980)

0% (2003)

0% (1982)

20% (1984)

30% (2004)

20% (1982)

20% (1993)