{
  "page": "compare",
  "query": {
    "a": "MGSIX",
    "b": "LUTAX"
  },
  "retrieved_at": "2026-07-07T17:52:31+00:00",
  "disclaimer": "Informational only — not investment advice. FundWatcher presents publicly available data and makes no recommendation to buy or sell any security. Verify all figures against the source filing before relying on them.",
  "attribution": "Data sourced from U.S. SEC EDGAR filings (Forms N-PORT, N-CEN, and prospectus Risk/Return summaries). FundWatcher is not affiliated with the SEC.",
  "terms": {
    "notice": "Use of this data is subject to the FundWatcher Terms of Service. Information may be used only for personal, non-commercial research and may not be redistributed.",
    "url": "https://fundwatcher.app/terms/"
  },
  "fund_a": {
    "name": "MFS Government Securities Fund",
    "ticker": "MGSIX",
    "slug": "MGSIX",
    "series_id": "S000000693",
    "html_url": "https://fundwatcher.app/funds/MGSIX/"
  },
  "fund_b": {
    "name": "Columbia U.S. Treasury Index Fund",
    "ticker": "LUTAX",
    "slug": "LUTAX",
    "series_id": "S000012098",
    "html_url": "https://fundwatcher.app/funds/LUTAX/"
  },
  "overlap": {
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    "coverage_b_by_a": "0.08941167950954488268174595217",
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  "error": null,
  "sources": [
    {
      "label": "N-PORT (fund A)",
      "accession_no": "0002071691-26-008227",
      "as_of": "2026-02-28",
      "edgar_url": "https://www.sec.gov/Archives/edgar/data/356349/000207169126008227/0002071691-26-008227-index.htm"
    },
    {
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      "accession_no": "0001410368-26-033335",
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      "edgar_url": "https://www.sec.gov/Archives/edgar/data/773757/000141036826033335/0001410368-26-033335-index.htm"
    }
  ]
}