{
  "page": "compare",
  "query": {
    "a": "MBOIX",
    "b": "FUTBX"
  },
  "retrieved_at": "2026-07-07T19:23:49+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": "Madison Core Bond Fund",
    "ticker": "MBOIX",
    "slug": "MBOIX",
    "series_id": "S000020646",
    "html_url": "https://fundwatcher.app/funds/MBOIX/"
  },
  "fund_b": {
    "name": "Fidelity SAI U.S. Treasury Bond Index Fund",
    "ticker": "FUTBX",
    "slug": "FUTBX",
    "series_id": "S000052911",
    "html_url": "https://fundwatcher.app/funds/FUTBX/"
  },
  "overlap": {
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    "coverage_b_by_a": "0.07460323754424047698733724397",
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    "as_of": {
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      "b": "2026-02-28"
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  "error": null,
  "sources": [
    {
      "label": "N-PORT (fund A)",
      "accession_no": "0001410368-26-064089",
      "as_of": "2026-04-30",
      "edgar_url": "https://www.sec.gov/Archives/edgar/data/1040612/000141036826064089/0001410368-26-064089-index.htm"
    },
    {
      "label": "N-PORT (fund B)",
      "accession_no": "0000035402-26-002620",
      "as_of": "2026-02-28",
      "edgar_url": "https://www.sec.gov/Archives/edgar/data/35315/000003540226002620/0000035402-26-002620-index.htm"
    }
  ]
}