20% (1988)

38% (1980)

36% (1979)

57% (1972)

10% (1969)

49% (1970)

20% (1992)

43% (1973)

20% (1993)

45% (1981)

48% (1984)

42% (1990)

37% (1984)

20% (1985)

0% (1993)

0% (1995)

55% (1969)

58% (1981)

20% (1979)

10% (1995)