65% (1981)

70% (1974)

59% (1979)

60% (1981)

51% (1990)

61% (1978)

59% (1976)

61% (1977)

72% (1981)

40% (1992)

60% (1981)

56% (1982)

58% (1974)

50% (1968)

57% (1983)

53% (1982)

57% (1977)

41% (1964)

58% (1980)

46% (1984)