{
  "page": "compare",
  "query": {
    "a": "SSMHX",
    "b": "FSMAX"
  },
  "retrieved_at": "2026-07-07T18:52:18+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": "STATE STREET SMALL/MID CAP EQUITY INDEX PORTFOLIO",
    "ticker": "SSMHX",
    "slug": "SSMHX",
    "series_id": "S000050332",
    "html_url": "https://fundwatcher.app/funds/SSMHX/"
  },
  "fund_b": {
    "name": "Fidelity Extended Market Index Fund",
    "ticker": "FSMAX",
    "slug": "FSMAX",
    "series_id": "S000006021",
    "html_url": "https://fundwatcher.app/funds/FSMAX/"
  },
  "overlap": {
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    "coverage_b_by_a": "0.8420714169955640590826728821",
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        "name": "HEICO CORP CL A",
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  },
  "error": null,
  "sources": [
    {
      "label": "N-PORT (fund A)",
      "accession_no": "0001410368-26-055491",
      "as_of": "2026-03-31",
      "edgar_url": "https://www.sec.gov/Archives/edgar/data/1107414/000141036826055491/0001410368-26-055491-index.htm"
    },
    {
      "label": "N-PORT (fund B)",
      "accession_no": "0000035402-26-002587",
      "as_of": "2026-02-28",
      "edgar_url": "https://www.sec.gov/Archives/edgar/data/819118/000003540226002587/0000035402-26-002587-index.htm"
    }
  ]
}