{
  "studyId": "RSR-003",
  "title": "The After-Dark Clock",
  "sourceKind": "official_public_records",
  "period": "2023-07-01 through 2026-06-30",
  "sampleSize": 116814,
  "methodology": [
    "Joined each SPD offense date to the official USNO solar record for Seattle.",
    "Classified recorded offense time as daylight, civil twilight, or night.",
    "Normalized counts by the number of calendar hours in each light phase."
  ],
  "findings": [
    "51.9% of accepted property-offense records were recorded outside the sunrise-to-sunset window.",
    "Night recorded 4771.15 offenses per 1,000 clock-hours versus 4186.82 during daylight."
  ],
  "metrics": {
    "acceptedOffenseRecords": 116814,
    "excluded": 0,
    "exactMidnightRecords": 10156,
    "phaseCounts": {
      "daylight": 56178,
      "twilight": 5129,
      "night": 55507
    },
    "calendarHours": {
      "daylight": 13417.8,
      "twilight": 1252.3,
      "night": 11633.9
    },
    "recordsPerThousandPhaseHours": {
      "daylight": 4186.82,
      "twilight": 4095.66,
      "night": 4771.15
    },
    "outsideDaylightWindowShare": 51.9,
    "nightToDayRateRatio": {
      "ratio": 1.14,
      "low": 1.126,
      "high": 1.153
    },
    "midnightSensitivity": [
      {
        "treatment": "retained-as-recorded",
        "includedRecords": 116814,
        "phaseCounts": {
          "daylight": 56178,
          "twilight": 5129,
          "night": 55507
        },
        "rates": {
          "daylight": 4186.82,
          "twilight": 4095.66,
          "night": 4771.15
        },
        "nightToDayRateRatio": 1.14,
        "conclusion": "night-rate-higher"
      },
      {
        "treatment": "excluded",
        "includedRecords": 106658,
        "phaseCounts": {
          "daylight": 56178,
          "twilight": 5129,
          "night": 45351
        },
        "rates": {
          "daylight": 4186.82,
          "twilight": 4095.66,
          "night": 3898.18
        },
        "nightToDayRateRatio": 0.931,
        "conclusion": "night-rate-not-higher"
      },
      {
        "treatment": "treated-as-unknown",
        "includedRecords": 106658,
        "unknownRecords": 10156,
        "phaseCounts": {
          "daylight": 56178,
          "twilight": 5129,
          "night": 45351
        },
        "rates": {
          "daylight": 4186.82,
          "twilight": 4095.66,
          "night": 3898.18
        },
        "nightToDayRateRatio": 0.931,
        "conclusion": "night-rate-not-higher"
      },
      {
        "treatment": "redistributed-from-known-times",
        "includedRecords": 116814,
        "phaseCounts": {
          "daylight": 61527.3,
          "twilight": 5617.4,
          "night": 49669.3
        },
        "rates": {
          "daylight": 4585.49,
          "twilight": 4485.65,
          "night": 4269.37
        },
        "nightToDayRateRatio": 0.931,
        "conclusion": "night-rate-not-higher"
      }
    ],
    "hourly": [
      {
        "hour": 0,
        "records": 12409
      },
      {
        "hour": 1,
        "records": 4532
      },
      {
        "hour": 2,
        "records": 3282
      },
      {
        "hour": 3,
        "records": 3509
      },
      {
        "hour": 4,
        "records": 3209
      },
      {
        "hour": 5,
        "records": 2923
      },
      {
        "hour": 6,
        "records": 2592
      },
      {
        "hour": 7,
        "records": 2688
      },
      {
        "hour": 8,
        "records": 3550
      },
      {
        "hour": 9,
        "records": 3466
      },
      {
        "hour": 10,
        "records": 3934
      },
      {
        "hour": 11,
        "records": 3979
      },
      {
        "hour": 12,
        "records": 4930
      },
      {
        "hour": 13,
        "records": 4203
      },
      {
        "hour": 14,
        "records": 4463
      },
      {
        "hour": 15,
        "records": 4929
      },
      {
        "hour": 16,
        "records": 5388
      },
      {
        "hour": 17,
        "records": 6613
      },
      {
        "hour": 18,
        "records": 6985
      },
      {
        "hour": 19,
        "records": 6239
      },
      {
        "hour": 20,
        "records": 6366
      },
      {
        "hour": 21,
        "records": 5618
      },
      {
        "hour": 22,
        "records": 6013
      },
      {
        "hour": 23,
        "records": 4994
      }
    ],
    "relativeToSunset": [
      {
        "startMinutes": -720,
        "endMinutes": -660,
        "records": 3322
      },
      {
        "startMinutes": -660,
        "endMinutes": -600,
        "records": 3433
      },
      {
        "startMinutes": -600,
        "endMinutes": -540,
        "records": 3649
      },
      {
        "startMinutes": -540,
        "endMinutes": -480,
        "records": 4018
      },
      {
        "startMinutes": -480,
        "endMinutes": -420,
        "records": 3996
      },
      {
        "startMinutes": -420,
        "endMinutes": -360,
        "records": 4209
      },
      {
        "startMinutes": -360,
        "endMinutes": -300,
        "records": 4429
      },
      {
        "startMinutes": -300,
        "endMinutes": -240,
        "records": 4953
      },
      {
        "startMinutes": -240,
        "endMinutes": -180,
        "records": 5381
      },
      {
        "startMinutes": -180,
        "endMinutes": -120,
        "records": 5767
      },
      {
        "startMinutes": -120,
        "endMinutes": -60,
        "records": 6018
      },
      {
        "startMinutes": -60,
        "endMinutes": 0,
        "records": 6396
      },
      {
        "startMinutes": 0,
        "endMinutes": 60,
        "records": 6577
      },
      {
        "startMinutes": 60,
        "endMinutes": 120,
        "records": 6342
      },
      {
        "startMinutes": 120,
        "endMinutes": 180,
        "records": 6759
      },
      {
        "startMinutes": 180,
        "endMinutes": 240,
        "records": 7234
      },
      {
        "startMinutes": 240,
        "endMinutes": 300,
        "records": 6224
      },
      {
        "startMinutes": 300,
        "endMinutes": 360,
        "records": 5115
      },
      {
        "startMinutes": 360,
        "endMinutes": 420,
        "records": 4778
      },
      {
        "startMinutes": 420,
        "endMinutes": 480,
        "records": 5813
      },
      {
        "startMinutes": 480,
        "endMinutes": 540,
        "records": 3452
      },
      {
        "startMinutes": 540,
        "endMinutes": 600,
        "records": 2947
      },
      {
        "startMinutes": 600,
        "endMinutes": 660,
        "records": 2904
      },
      {
        "startMinutes": 660,
        "endMinutes": 720,
        "records": 3098
      }
    ],
    "byMonth": [
      {
        "label": "2023-07",
        "counts": {
          "daylight": 2439,
          "twilight": 186,
          "night": 1256
        }
      },
      {
        "label": "2023-08",
        "counts": {
          "daylight": 2205,
          "twilight": 171,
          "night": 1453
        }
      },
      {
        "label": "2023-09",
        "counts": {
          "daylight": 1830,
          "twilight": 120,
          "night": 1584
        }
      },
      {
        "label": "2023-10",
        "counts": {
          "daylight": 1590,
          "twilight": 142,
          "night": 1816
        }
      },
      {
        "label": "2023-11",
        "counts": {
          "daylight": 1273,
          "twilight": 185,
          "night": 2100
        }
      },
      {
        "label": "2023-12",
        "counts": {
          "daylight": 1064,
          "twilight": 123,
          "night": 2294
        }
      },
      {
        "label": "2024-01",
        "counts": {
          "daylight": 1082,
          "twilight": 157,
          "night": 1957
        }
      },
      {
        "label": "2024-02",
        "counts": {
          "daylight": 1139,
          "twilight": 153,
          "night": 1500
        }
      },
      {
        "label": "2024-03",
        "counts": {
          "daylight": 1588,
          "twilight": 120,
          "night": 1442
        }
      },
      {
        "label": "2024-04",
        "counts": {
          "daylight": 1769,
          "twilight": 108,
          "night": 1170
        }
      },
      {
        "label": "2024-05",
        "counts": {
          "daylight": 2084,
          "twilight": 184,
          "night": 1137
        }
      },
      {
        "label": "2024-06",
        "counts": {
          "daylight": 1990,
          "twilight": 119,
          "night": 1021
        }
      },
      {
        "label": "2024-07",
        "counts": {
          "daylight": 2148,
          "twilight": 149,
          "night": 1228
        }
      },
      {
        "label": "2024-08",
        "counts": {
          "daylight": 2141,
          "twilight": 173,
          "night": 1434
        }
      },
      {
        "label": "2024-09",
        "counts": {
          "daylight": 1981,
          "twilight": 171,
          "night": 1835
        }
      },
      {
        "label": "2024-10",
        "counts": {
          "daylight": 1629,
          "twilight": 174,
          "night": 2309
        }
      },
      {
        "label": "2024-11",
        "counts": {
          "daylight": 1246,
          "twilight": 182,
          "night": 2227
        }
      },
      {
        "label": "2024-12",
        "counts": {
          "daylight": 1139,
          "twilight": 129,
          "night": 2260
        }
      },
      {
        "label": "2025-01",
        "counts": {
          "daylight": 1075,
          "twilight": 168,
          "night": 1951
        }
      },
      {
        "label": "2025-02",
        "counts": {
          "daylight": 952,
          "twilight": 133,
          "night": 1354
        }
      },
      {
        "label": "2025-03",
        "counts": {
          "daylight": 1243,
          "twilight": 127,
          "night": 1358
        }
      },
      {
        "label": "2025-04",
        "counts": {
          "daylight": 1581,
          "twilight": 115,
          "night": 1103
        }
      },
      {
        "label": "2025-05",
        "counts": {
          "daylight": 1975,
          "twilight": 175,
          "night": 1092
        }
      },
      {
        "label": "2025-06",
        "counts": {
          "daylight": 1853,
          "twilight": 124,
          "night": 961
        }
      },
      {
        "label": "2025-07",
        "counts": {
          "daylight": 1863,
          "twilight": 119,
          "night": 1067
        }
      },
      {
        "label": "2025-08",
        "counts": {
          "daylight": 1784,
          "twilight": 160,
          "night": 1426
        }
      },
      {
        "label": "2025-09",
        "counts": {
          "daylight": 1565,
          "twilight": 126,
          "night": 1488
        }
      },
      {
        "label": "2025-10",
        "counts": {
          "daylight": 1444,
          "twilight": 133,
          "night": 1844
        }
      },
      {
        "label": "2025-11",
        "counts": {
          "daylight": 1035,
          "twilight": 146,
          "night": 1749
        }
      },
      {
        "label": "2025-12",
        "counts": {
          "daylight": 1023,
          "twilight": 103,
          "night": 2227
        }
      },
      {
        "label": "2026-01",
        "counts": {
          "daylight": 1018,
          "twilight": 142,
          "night": 2057
        }
      },
      {
        "label": "2026-02",
        "counts": {
          "daylight": 948,
          "twilight": 105,
          "night": 1379
        }
      },
      {
        "label": "2026-03",
        "counts": {
          "daylight": 1296,
          "twilight": 121,
          "night": 1292
        }
      },
      {
        "label": "2026-04",
        "counts": {
          "daylight": 1490,
          "twilight": 116,
          "night": 1137
        }
      },
      {
        "label": "2026-05",
        "counts": {
          "daylight": 1852,
          "twilight": 152,
          "night": 1087
        }
      },
      {
        "label": "2026-06",
        "counts": {
          "daylight": 1844,
          "twilight": 118,
          "night": 912
        }
      }
    ],
    "byWeekpart": [
      {
        "label": "weekend",
        "counts": {
          "daylight": 15365,
          "twilight": 1384,
          "night": 16466
        }
      },
      {
        "label": "weekday",
        "counts": {
          "daylight": 40813,
          "twilight": 3745,
          "night": 39041
        }
      }
    ],
    "byOffenseSubcategory": [
      {
        "label": "LARCENY-THEFT",
        "counts": {
          "daylight": 37078,
          "twilight": 2940,
          "night": 30303
        }
      },
      {
        "label": "BURGLARY",
        "counts": {
          "daylight": 9289,
          "twilight": 1142,
          "night": 14521
        }
      },
      {
        "label": "MOTOR VEHICLE THEFT",
        "counts": {
          "daylight": 9630,
          "twilight": 1022,
          "night": 10398
        }
      },
      {
        "label": "ARSON",
        "counts": {
          "daylight": 181,
          "twilight": 25,
          "night": 285
        }
      }
    ]
  },
  "limitations": [
    "Recorded offense start time may be approximate, especially exact-midnight records.",
    "Calendar-time normalization is not a measure of property exposure or individual risk."
  ]
}