57% (1980)

47% (1991)

55% (1973)

54% (1980)

41% (1983)

58% (1974)

53% (1975)

40% (1976)

48% (1980)

65% (1976)

46% (1977)

42% (1974)

50% (1991)

48% (1980)

50% (1976)

50% (1983)

62% (1975)

20% (2002)

61% (1997)

40% (1980)