53% (1976)

63% (1973)

75% (1969)

72% (1970)

47% (1976)

63% (1973)

62% (1975)

66% (1971)

61% (1973)

65% (1974)

47% (1973)

65% (1976)

61% (1974)

51% (1972)

63% (1971)

62% (1974)

47% (1970)

60% (1975)

59% (1974)

54% (1974)