{
  "id": "income-migration-destinations",
  "question": "Where did returns leaving King County move?",
  "hint": "Named states and suppression bounds",
  "answer": "California was the largest single interstate destination, with 8,477 named returns. That single-state ranking survives the reviewed suppression bounds.",
  "period": "Calendar-year filing transition 2022-2023",
  "limit": "Matched filing-address returns are not individual people. Class and amount use year-2 income. This earlier transition differs from the dividend comparison; aggregate AGI does not identify dividend income, tax motive or a causal mechanism. Region-only rows cannot be assigned to states.",
  "status": "reviewed",
  "children": [],
  "related": [
    "income-migration-classes"
  ],
  "findings": [
    {
      "id": "income-finding-destinations",
      "title": "A robust single-state result, a limited combined comparison",
      "text": "Nevada, Florida and Texas have 5,459 identified returns combined. Suppressed region-only rows make their combined comparison with California indeterminate.",
      "limits": [
        "45 named destination jurisdictions are shown. Region-only suppression buckets remain separate.",
        "The files do not establish disproportionate destination representation or tax motive."
      ],
      "source_url": "https://www.irs.gov/pub/irs-soi/countyoutflow2223.csv"
    }
  ],
  "plots": [
    {
      "id": "income-plot-king-destinations",
      "title": "King County interstate outflow returns",
      "caption": "All 45 named destination jurisdictions and four region-only suppression buckets. California remains the largest single destination under the reviewed bounds. Suppression prevents a definitive comparison with Nevada, Florida and Texas combined.",
      "alt": "Horizontal bars for all 45 named King County interstate destination jurisdictions and four separate region-only suppression buckets. California has 8,477 named returns.",
      "image_url": "/research/washington-income/2026-09-21/charts/king-destinations-penner-strategy.svg",
      "download_url": "/research/washington-income/2026-09-21/charts/king-destinations-penner-strategy.svg",
      "data_url": "/research/washington-income/2026-09-21/data/king-destinations.csv",
      "record_url": "/research/washington-income/2026-09-21/nodes/income-migration-destinations/index.html"
    }
  ],
  "sources": [
    {
      "label": "IRS county outflow, CY2022-2023",
      "url": "https://www.irs.gov/pub/irs-soi/countyoutflow2223.csv"
    },
    {
      "label": "IRS migration data and documentation, 2022-2023",
      "url": "https://www.irs.gov/statistics/soi-tax-stats-migration-data-2022-2023"
    }
  ],
  "record_url": "/research/washington-income/2026-09-21/nodes/income-migration-destinations/index.html",
  "as_of_date": "2026-09-21",
  "methods": "Aggregate named destination rows and bound compatible suppressed region totals without assigning them to particular states.",
  "lineage_ids": [
    "E-c1bfe70d8b0b"
  ],
  "publication_state": "prepared",
  "record_json_url": "/research/washington-income/2026-09-21/nodes/income-migration-destinations/record.json"
}