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    {
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    {
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    {
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    {
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    {
      "from_contract": "ZLZ25-CBOT",
      "to_contract": "ZLF26-CBOT",
      "decision_session": "2025-11-19",
      "old_volume": 40399,
      "new_volume": 68171,
      "switch_utc": "2025-11-19T23:00:00+00:00",
      "difference": 0.3200000000000003
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    {
      "from_contract": "ZLF26-CBOT",
      "to_contract": "ZLH26-CBOT",
      "decision_session": "2025-12-16",
      "old_volume": 55690,
      "new_volume": 58482,
      "switch_utc": "2025-12-16T23:00:00+00:00",
      "difference": 0.5400000000000063
    },
    {
      "from_contract": "ZLH26-CBOT",
      "to_contract": "ZLK26-CBOT",
      "decision_session": "2026-02-18",
      "old_volume": 40443,
      "new_volume": 60936,
      "switch_utc": "2026-02-18T23:00:00+00:00",
      "difference": 0.490000000000002
    },
    {
      "from_contract": "ZLK26-CBOT",
      "to_contract": "ZLN26-CBOT",
      "decision_session": "2026-04-16",
      "old_volume": 41042,
      "new_volume": 47431,
      "switch_utc": "2026-04-16T22:00:00+00:00",
      "difference": -0.29000000000000625
    },
    {
      "from_contract": "ZLN26-CBOT",
      "to_contract": "ZLQ26-CBOT",
      "decision_session": "2026-06-24",
      "old_volume": 18316,
      "new_volume": 20814,
      "switch_utc": "2026-06-24T22:00:00+00:00",
      "difference": -1.190000000000012
    },
    {
      "from_contract": "ZLQ26-CBOT",
      "to_contract": "ZLU26-CBOT",
      "decision_session": "2026-07-22",
      "old_volume": 14220,
      "new_volume": 14382,
      "switch_utc": "2026-07-22T22:00:00+00:00",
      "difference": -0.9599999999999937
    },
    {
      "from_contract": "ZLU26-CBOT",
      "to_contract": "ZLV26-CBOT",
      "decision_session": "2026-08-24",
      "old_volume": 18541,
      "new_volume": 20537,
      "switch_utc": "2026-08-24T22:00:00+00:00",
      "difference": 0.15000000000000568
    },
    {
      "from_contract": "ZLV26-CBOT",
      "to_contract": "ZLZ26-CBOT",
      "decision_session": "2026-09-09",
      "old_volume": 11633,
      "new_volume": 35758,
      "switch_utc": "2026-09-09T22:00:00+00:00",
      "difference": 0.5
    }
  ]
}