54% (1992)

54% (1981)

65% (1980)

66% (1972)

53% (1980)

62% (1972)

46% (1986)

51% (1972)

53% (1988)

55% (1987)

54% (1986)

54% (1984)

48% (1976)

60% (1971)

52% (1979)

52% (1987)

32% (1989)

55% (1984)

42% (1988)

39% (1989)