1955

83.08

16.92

65.77

34.23

1965

79.26

20.74

67.50

32.50

1975

76.51

23.49

75.86

24.14

1985

56

44

59.6

40.4

1986

54

46

57.6

42.4

1987

52

48

57.4

42.6

1988

50

50

57.1

42.9

1989

50

50

57.4

42.6

1990

51

49

57.6

42.4

1991

52

48

59.2

40.8

1992

50

50

60.0

40.0

1993

48

52

59.0

41.0

1994

47

53

58.0

42.0

1995

46

54

57.2

42.8

1996

46

54

55.5

44.5

1997

43.70

56.30

60.43

39.57

1998

44.15

55.85

60.33

39.67