1. 1976.
    0
    up up up up
    ···
  2. 1977.
    0
    up up up up
    ···
  3. 1978.
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    up up up up
    ···
  4. 1979.
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    ···
  5. 1980.
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    ···
  6. 1981.
    0
    up up up up
    ···
  7. 1982.
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    ···
  8. 1983.
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    up up up up
    ···
  9. 1984.
    0
    up up up up
    ···
  10. 1985.
    0
    up up up up
    ···
  11. 1986.
    0
    up up up up
    ···
  12. 1987.
    0
    up up up up
    ···
  13. 1988.
    0
    up up up up
    ···
  14. 1989.
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    up up up up
    ···
  15. 1990.
    0
    up up up up
    ···
  16. 1991.
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    up up up up
    ···
  17. 1992.
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    up up up up
    ···
  18. 1993.
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    up up up up
    ···
  19. 1994.
    0
    up up up up
    ···
  20. 1995.
    0
    up up up up
    ···