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      "switch_utc": "2018-04-18T22:00:00+00:00",
      "difference": 0.11500000000000021
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      "difference": 0.05749999999999922
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      "difference": 0.11500000000000021
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      "difference": 0.13250000000000028
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      "decision_session": "2018-12-21",
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      "difference": 0.13250000000000028
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      "decision_session": "2019-02-22",
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      "switch_utc": "2019-02-24T23:00:00+00:00",
      "difference": 0.13250000000000028
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      "difference": 0.13000000000000078
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      "difference": 0.0600000000000005
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      "difference": 0.054999999999999716
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      "difference": 0.1274999999999995
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      "difference": 0.14499999999999957
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      "difference": 0.07750000000000057
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      "difference": 0.08249999999999957
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      "difference": 0.09750000000000014
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      "difference": -0.04749999999999943
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      "difference": 0.030000000000001137
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      "difference": -0.042500000000000426
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      "difference": 0.042500000000000426
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      "decision_session": "2021-02-22",
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      "difference": 0.03250000000000064
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      "decision_session": "2021-04-16",
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      "difference": -0.11249999999999893
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      "difference": -0.20749999999999957
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      "difference": -0.5075000000000003
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      "difference": 0.09750000000000014
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      "difference": 0.015000000000000568
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      "switch_utc": "2022-02-22T23:00:00+00:00",
      "difference": 0.0
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      "difference": -1.125
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      "difference": -1.1524999999999999
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      "difference": -0.8275000000000006
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      "difference": 0.08750000000000036
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      "switch_utc": "2022-12-21T23:00:00+00:00",
      "difference": 0.040000000000000924
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      "decision_session": "2023-02-21",
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      "difference": -0.04749999999999943
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    {
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      "decision_session": "2023-04-17",
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      "switch_utc": "2023-04-17T22:00:00+00:00",
      "difference": -0.3100000000000005
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    {
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      "decision_session": "2023-06-26",
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      "difference": -0.9675000000000011
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    {
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      "difference": -0.6925000000000008
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    {
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      "decision_session": "2023-08-14",
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      "switch_utc": "2023-08-14T22:00:00+00:00",
      "difference": -0.2624999999999993
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    {
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      "switch_utc": "2023-10-25T22:00:00+00:00",
      "difference": 0.1999999999999993
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    {
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      "decision_session": "2023-12-19",
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      "switch_utc": "2023-12-19T23:00:00+00:00",
      "difference": 0.09750000000000014
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    {
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      "decision_session": "2024-02-21",
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      "switch_utc": "2024-02-21T23:00:00+00:00",
      "difference": 0.040000000000000924
    },
    {
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      "decision_session": "2024-04-18",
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      "switch_utc": "2024-04-18T22:00:00+00:00",
      "difference": 0.14499999999999957
    },
    {
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      "decision_session": "2024-06-26",
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      "switch_utc": "2024-06-26T22:00:00+00:00",
      "difference": -0.1974999999999998
    },
    {
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      "decision_session": "2024-07-29",
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      "switch_utc": "2024-07-29T22:00:00+00:00",
      "difference": -0.2575000000000003
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    {
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      "decision_session": "2024-08-13",
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      "switch_utc": "2024-08-13T22:00:00+00:00",
      "difference": 0.15499999999999936
    },
    {
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      "decision_session": "2024-10-25",
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      "switch_utc": "2024-10-27T22:00:00+00:00",
      "difference": 0.09749999999999837
    },
    {
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      "to_contract": "ZSH25-CBOT",
      "decision_session": "2024-12-20",
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      "switch_utc": "2024-12-22T23:00:00+00:00",
      "difference": 0.04749999999999943
    },
    {
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      "decision_session": "2025-02-20",
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      "switch_utc": "2025-02-20T23:00:00+00:00",
      "difference": 0.17499999999999893
    },
    {
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      "to_contract": "ZSN25-CBOT",
      "decision_session": "2025-04-17",
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      "switch_utc": "2025-04-17T22:00:00+00:00",
      "difference": 0.10749999999999993
    },
    {
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      "decision_session": "2025-06-24",
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      "switch_utc": "2025-06-24T22:00:00+00:00",
      "difference": 0.03500000000000014
    },
    {
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      "to_contract": "ZSU25-CBOT",
      "decision_session": "2025-07-28",
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      "switch_utc": "2025-07-28T22:00:00+00:00",
      "difference": 0.040000000000000924
    },
    {
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      "to_contract": "ZSX25-CBOT",
      "decision_session": "2025-08-11",
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      "switch_utc": "2025-08-11T22:00:00+00:00",
      "difference": 0.19250000000000078
    },
    {
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      "to_contract": "ZSF26-CBOT",
      "decision_session": "2025-10-24",
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      "switch_utc": "2025-10-26T22:00:00+00:00",
      "difference": 0.1875
    },
    {
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      "to_contract": "ZSH26-CBOT",
      "decision_session": "2025-12-19",
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      "switch_utc": "2025-12-21T23:00:00+00:00",
      "difference": 0.10249999999999915
    },
    {
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      "to_contract": "ZSK26-CBOT",
      "decision_session": "2026-02-18",
      "old_volume": 51593,
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      "switch_utc": "2026-02-18T23:00:00+00:00",
      "difference": 0.15750000000000064
    },
    {
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      "to_contract": "ZSN26-CBOT",
      "decision_session": "2026-04-21",
      "old_volume": 43606,
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      "switch_utc": "2026-04-21T22:00:00+00:00",
      "difference": 0.16249999999999964
    },
    {
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      "to_contract": "ZSQ26-CBOT",
      "decision_session": "2026-06-29",
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      "switch_utc": "2026-06-29T22:00:00+00:00",
      "difference": 0.10749999999999993
    },
    {
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      "to_contract": "ZSU26-CBOT",
      "decision_session": "2026-07-27",
      "old_volume": 11504,
      "new_volume": 14072,
      "switch_utc": "2026-07-27T22:00:00+00:00",
      "difference": -0.08750000000000036
    },
    {
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      "to_contract": "ZSX26-CBOT",
      "decision_session": "2026-08-17",
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      "new_volume": 113737,
      "switch_utc": "2026-08-17T22:00:00+00:00",
      "difference": 0.15249999999999986
    }
  ]
}