{
  "page": "compare",
  "query": {
    "a": "MMIIX",
    "b": "RTHAX"
  },
  "retrieved_at": "2026-07-07T19:05:27+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 Municipal High Income Fund",
    "ticker": "MMIIX",
    "slug": "MMIIX",
    "series_id": "S000002429",
    "html_url": "https://fundwatcher.app/funds/MMIIX/"
  },
  "fund_b": {
    "name": "Tax-Exempt High Yield Bond Fund",
    "ticker": "RTHAX",
    "slug": "RTHAX",
    "series_id": "S000049244",
    "html_url": "https://fundwatcher.app/funds/RTHAX/"
  },
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    "coverage_b_by_a": "0.1271398101032410693461517912",
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    "as_of": {
      "a": "2026-04-30",
      "b": "2026-04-30"
    },
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      },
      {
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        "name": "TARRANT RETIRE 5.75% 12/1/2054",
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        "name": "METROHEALTH SYSTEM 5.5% 02-15-52",
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        "name": "SYRACUSE PILOT 5% 1/1/2034 @",
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      {
        "name": "BERKS PA MUN AU 3% 6/30/2044",
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      {
        "name": "Black Belt Energy Gas District, Series 2025 A",
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      {
        "name": "VIRGIN ISLANDS HOTEL DEV FING REGD OID B/E 6.00000000",
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    ],
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      {
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      {
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      {
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      {
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      {
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  "sources": [
    {
      "label": "N-PORT (fund A)",
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      "as_of": "2026-04-30",
      "edgar_url": "https://www.sec.gov/Archives/edgar/data/225604/000207169126015576/0002071691-26-015576-index.htm"
    },
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      "edgar_url": "https://www.sec.gov/Archives/edgar/data/351601/000141036826063588/0001410368-26-063588-index.htm"
    }
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}