71% (1989)

42% (1972)

58% (1976)

41% (1978)

51% (1978)

39% (1977)

50% (1973)

50% (1973)

45% (1983)

54% (1972)

48% (1980)

62% (1970)

50% (1975)

63% (1969)

42% (1980)

50% (1973)

62% (1970)

42% (1975)

53% (1971)

50% (1998)