61% (1999)

42% (1984)

62% (1976)

53% (1983)

52% (1999)

40% (1977)

56% (1998)

47% (1984)

68% (1990)

68% (1997)

67% (1977)

42% (1974)

30% (1971)

63% (1997)

77% (1986)

70% (1983)

61% (1976)

59% (1980)

62% (1981)

63% (1975)