{
  "page": "compare",
  "query": {
    "a": "MRBCX",
    "b": "VBLLX"
  },
  "retrieved_at": "2026-07-07T18:59:14+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 Total Return Bond Fund",
    "ticker": "MRBCX",
    "slug": "MRBCX",
    "series_id": "S000002497",
    "html_url": "https://fundwatcher.app/funds/MRBCX/"
  },
  "fund_b": {
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    "slug": "VBLLX",
    "series_id": "S000002562",
    "html_url": "https://fundwatcher.app/funds/VBLLX/"
  },
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  "sources": [
    {
      "label": "N-PORT (fund A)",
      "accession_no": "0002071691-26-015566",
      "as_of": "2026-04-30",
      "edgar_url": "https://www.sec.gov/Archives/edgar/data/63075/000207169126015566/0002071691-26-015566-index.htm"
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}