{
  "page": "compare",
  "query": {
    "a": "RMBEX",
    "b": "AMUSX"
  },
  "retrieved_at": "2026-07-07T15:05:10+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": "American Funds Mortgage Fund",
    "ticker": "RMBEX",
    "slug": "RMBEX",
    "series_id": "S000030190",
    "html_url": "https://fundwatcher.app/funds/RMBEX/"
  },
  "fund_b": {
    "name": "U.S. Government Securities Fund",
    "ticker": "AMUSX",
    "slug": "AMUSX",
    "series_id": "S000009235",
    "html_url": "https://fundwatcher.app/funds/AMUSX/"
  },
  "overlap": {
    "coverage_a_by_b": "0.3170583571233837972236312444",
    "coverage_b_by_a": "0.3170583571233837972236312441",
    "shared_count": 704,
    "as_of": {
      "a": "2026-02-28",
      "b": "2026-02-28"
    },
    "a_top": [
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        "name": "CAPITAL GROUP CENTRAL CASH FUND",
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      },
      {
        "name": "FHLBanks Office of Finance",
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      },
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      },
      {
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      },
      {
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      },
      {
        "name": "FHLBanks Office of Finance",
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      },
      {
        "name": "Federal Home Loan Bank Discount Notes",
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      },
      {
        "name": "Federal Home Loan Bank Discount Notes",
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      },
      {
        "name": "Federal Home Loan Bank (FHLB)",
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      },
      {
        "name": "FED HM LN BK BD 6/18/2026",
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      },
      {
        "name": "FED HOME LN DISCOUNT NT DISCOUNT NOT 03/26 0.00000",
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      {
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      },
      {
        "name": "FNMDI4 3.5 BF0765 09-01-63",
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      {
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      {
        "name": "FED HM LN BK BD 5/15/2026",
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        "name": "G2 MA7051",
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      {
        "name": "Federal Farm Credit, 03",
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      {
        "name": "FNCL UMBS 6.0 QX4065 01-01-55",
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      {
        "name": "UMBS, 30 Year",
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      {
        "name": "FED HOME LN DISCOUNT NT DISCOUNT NOT 03/26 0.00000",
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      {
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      {
        "name": "GOVERNMENT NATIONAL MORTGAGE CORPORATION",
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      },
      {
        "name": "Fannie Mae or Freddie Mac",
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      {
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        "name": "US TREASURY N/B",
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      {
        "name": "OIS RECFIX USD 4.9005% 04-17-24/04-17-26 LCH",
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      },
      {
        "name": "UNITED STATES TREASURY INFLATION INDEXED BONDS I/L 2.375% 02-15-56",
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    ]
  },
  "error": null,
  "sources": [
    {
      "label": "N-PORT (fund A)",
      "accession_no": "0001193125-26-182050",
      "as_of": "2026-02-28",
      "edgar_url": "https://www.sec.gov/Archives/edgar/data/1496998/000119312526182050/0001193125-26-182050-index.htm"
    },
    {
      "label": "N-PORT (fund B)",
      "accession_no": "0001193125-26-182060",
      "as_of": "2026-02-28",
      "edgar_url": "https://www.sec.gov/Archives/edgar/data/770161/000119312526182060/0001193125-26-182060-index.htm"
    }
  ]
}