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FRED

Federal Reserve Economic Data: macro series with point-in-time vintages, so a revised print never masquerades as the original.

llms.txt

Code

Full reference

10 endpoints · plain text

GET

Category/v1/finance:fred/category

2 params

Walk the FRED category tree: child categories at a node, and the series that

Parameters

categorynumberoptional: FRED category id. Omit for the root of the tree.
pagenumberoptional: Page of the series listing (default 1)

Request

curl -X GET "https://api.zapi.ink/v1/finance:fred/category?category=115&page=1" \
  -H "x-api-key: zpi_xxxxxxxxxxxxxxxxxxxxxxxx"

Example response

{
  "page": 1,
  "count": 50,
  "items": [
    {
      "url": "https://fred.stlouisfed.org/series/DGS10",
      "title": "Market Yield on U.S. Treasury Securities at 10-Year Constant Maturity, Quoted on an Investment Basis",
      "units": "Percent",
      "series": "DGS10",
      "frequency": "Daily",
      "observationEnd": "2026-08-18",
      "observationStart": "1962-01-02",
      "seasonalAdjustment": "Not Seasonally Adjusted"
    },
    {
      "url": "https://fred.stlouisfed.org/series/GS10",
      "title": "Market Yield on U.S. Treasury Securities at 10-Year Constant Maturity, Quoted on an Investment Basis",
      "units": "Percent",
      "series": "GS10",
      "frequency": "Monthly",
      "observationEnd": "Jul 2026",
      "observationStart": "Apr 1953",
      "seasonalAdjustment": "Not Seasonally Adjusted"
    },
    {
      "url": "https://fred.stlouisfed.org/series/WGS10YR",
      "title": "Market Yield on U.S. Treasury Securities at 10-Year Constant Maturity, Quoted on an Investment Basis",
      "units": "Percent",
      "series": "WGS10YR",
      "frequency": "Weekly",
      "observationEnd": "2026-08-14",
      "observationStart": "1962-01-05",
      "seasonalAdjustment": "Not Seasonally Adjusted"
    }
  ],
  "total": null,
  "dataset": "category",
  "hasMore": true,
  "category": 115,
  "children": [
    {
      "name": "Money, Banking, & Finance",
      "categoryId": 32991
    },
    {
      "name": "Interest Rates",
      "categoryId": 22
    }
  ],
  "nextPage": 2,
  "provider": "fred"
}

GET

Observations Vintage/v1/finance:fred/observations-vintage

5 params

Point-in-time observations — what a series looked like on the day it was

Parameters

seriesstringoptional: FRED series ids, comma-separated. A missing observation comes back as null, never 0. Default GDP.
vintagesstringoptional: Vintage dates, comma-separated, YYYY-MM-DD. List them with the vintage-dates endpoint. Series times vintages must not exceed 12. Defaults to the latest vintage.
fromstringoptional: First observation date, YYYY-MM-DD.
tostringoptional: Last observation date, YYYY-MM-DD.
lengthnumberoptional: Observations to return, newest first (default 100, max 20000)

Request

curl -X GET "https://api.zapi.ink/v1/finance:fred/observations-vintage?series=GDP&vintages=2020-01-30%2C2020-04-29%2C2026-07-30&from=2019-07-01&to=2019-12-31&length=100" \
  -H "x-api-key: zpi_xxxxxxxxxxxxxxxxxxxxxxxx"

Example response

{
  "to": "2019-12-31",
  "from": "2019-07-01",
  "count": 2,
  "items": [
    {
      "date": "2019-10-01",
      "values": {
        "GDP": 21933.217
      }
    },
    {
      "date": "2019-07-01",
      "values": {
        "GDP": 21717.171
      }
    }
  ],
  "total": 2,
  "series": [
    "GDP"
  ],
  "columns": [
    {
      "key": "GDP",
      "column": "GDP_20260820",
      "series": "GDP"
    }
  ],
  "dataset": "observations-vintage",
  "missing": [],
  "provider": "fred",
  "vintages": []
}

GET

Release Dates/v1/finance:fred/release-dates

5 params

The US statistical release calendar — what is published on a given day, at what

Parameters

fromstringoptional: First calendar date, YYYY-MM-DD. Defaults to today.
tostringoptional: Last calendar date, YYYY-MM-DD. Defaults to from.
releasenumberoptional: Restrict to one release id, from the releases endpoint.
yearnumberoptional: Whole calendar year. Use with release; overrides from/to.
pagenumberoptional: Page of the calendar, 50 entries each (default 1)

Request

curl -X GET "https://api.zapi.ink/v1/finance:fred/release-dates?from=2026-08-17&to=2026-08-21&release=18&year=2026&page=1" \
  -H "x-api-key: zpi_xxxxxxxxxxxxxxxxxxxxxxxx"

Example response

{
  "to": "2026-08-21",
  "from": "2026-08-17",
  "page": 1,
  "year": 2026,
  "count": 50,
  "items": [
    {
      "url": "https://fred.stlouisfed.org/release?rid=18",
      "date": "2026-01-02",
      "name": "H.15 Selected Interest Rates",
      "time": "3:15 pm",
      "released": true,
      "releaseId": 18
    },
    {
      "url": "https://fred.stlouisfed.org/release?rid=18",
      "date": "2026-01-05",
      "name": "H.15 Selected Interest Rates",
      "time": "3:15 pm",
      "released": true,
      "releaseId": 18
    },
    {
      "url": "https://fred.stlouisfed.org/release?rid=18",
      "date": "2026-01-06",
      "name": "H.15 Selected Interest Rates",
      "time": "3:15 pm",
      "released": true,
      "releaseId": 18
    },
    {
      "url": "https://fred.stlouisfed.org/release?rid=18",
      "date": "2026-01-07",
      "name": "H.15 Selected Interest Rates",
      "time": "3:15 pm",
      "released": true,
      "releaseId": 18
    },
    {
      "url": "https://fred.stlouisfed.org/release?rid=18",
      "date": "2026-01-08",
      "name": "H.15 Selected Interest Rates",
      "time": "3:15 pm",
      "released": true,
      "releaseId": 18
    },
    {
      "url": "https://fred.stlouisfed.org/release?rid=18",
      "date": "2026-01-09",
      "name": "H.15 Selected Interest Rates",
      "time": "3:15 pm",
      "released": true,
      "releaseId": 18
    }
  ],
  "total": null,
  "dataset": "release-dates",
  "hasMore": true,
  "release": 18,
  "nextPage": 2,
  "provider": "fred"
}

GET

Releases/v1/finance:fred/releases

2 params

The release catalogue — every statistical publication FRED redistributes,

Parameters

pagenumberoptional: Catalogue page, 50 releases each (default 1)
querystringoptional: Keep only releases whose name contains this text.

Request

curl -X GET "https://api.zapi.ink/v1/finance:fred/releases?page=1&query=interest+rates" \
  -H "x-api-key: zpi_xxxxxxxxxxxxxxxxxxxxxxxx"

Example response

{
  "page": 1,
  "count": 4,
  "items": [
    {
      "url": "https://fred.stlouisfed.org/release?rid=131",
      "name": "G.13 Selected Interest Rates",
      "releaseId": 131
    },
    {
      "url": "https://fred.stlouisfed.org/release?rid=18",
      "name": "H.15 Selected Interest Rates",
      "releaseId": 18
    },
    {
      "url": "https://fred.stlouisfed.org/release?rid=484",
      "name": "Key ECB Interest Rates",
      "releaseId": 484
    },
    {
      "url": "https://fred.stlouisfed.org/release?rid=94",
      "name": "Survey of Secondary Market Prices and Yields, and Interest Rates for Home Loans",
      "releaseId": 94
    }
  ],
  "query": "interest rates",
  "total": null,
  "dataset": "releases",
  "hasMore": false,
  "nextPage": null,
  "provider": "fred"
}

GET

Series Observations/v1/finance:fred/series-observations

7 params

FRED observations — any economic series the St. Louis Fed publishes, by id.

Parameters

seriesstringoptional: FRED series ids, comma-separated, up to 12 — the upstream drops the 13th silently. A missing observation comes back as null, never 0. Default DGS10.
fromstringoptional: First observation date, YYYY-MM-DD. Applied to every series.
tostringoptional: Last observation date, YYYY-MM-DD. Applied to every series.
transformationenumoptional: Server-side transform: lin (level), chg, ch1, pch, pc1 (year-over-year %), pca, cch, cca, log. Default lin. Values: lin, chg, ch1, pch, pc1, pca, cch, cca, log.
frequencyenumoptional: Resample a higher-frequency series down to Daily, Weekly, Biweekly, Monthly, Quarterly, Semiannual or Annual. Values: Daily, Weekly, Biweekly, Monthly, Quarterly, Semiannual, Annual.
aggregationenumoptional: How frequency collapses each bucket: avg, sum or eop (end of period). Default avg. Values: avg, sum, eop.
lengthnumberoptional: Observations to return, newest first (default 100, max 20000)

Request

curl -X GET "https://api.zapi.ink/v1/finance:fred/series-observations?series=DGS10%2CDGS2%2CT10Y2Y&from=2026-01-01&to=2026-08-18&transformation=pc1&frequency=Monthly&aggregation=avg&length=100" \
  -H "x-api-key: zpi_xxxxxxxxxxxxxxxxxxxxxxxx"

Example response

{
  "to": "2026-08-01",
  "from": "2024-01-01",
  "count": 100,
  "items": [
    {
      "date": "2026-07-31",
      "values": {
        "DFII10": 2.47
      }
    },
    {
      "date": "2026-07-30",
      "values": {
        "DFII10": 2.41
      }
    },
    {
      "date": "2026-07-29",
      "values": {
        "DFII10": 2.41
      }
    },
    {
      "date": "2026-07-28",
      "values": {
        "DFII10": 2.41
      }
    },
    {
      "date": "2026-07-27",
      "values": {
        "DFII10": 2.44
      }
    },
    {
      "date": "2026-07-24",
      "values": {
        "DFII10": 2.43
      }
    }
  ],
  "total": 674,
  "series": [
    "DFII10"
  ],
  "dataset": "series-observations",
  "missing": [],
  "provider": "fred",
  "resolved": [
    "DFII10"
  ],
  "transformation": "lin"
}

GET

Series Search/v1/finance:fred/series-search

3 params

Free-text search across the FRED catalogue — the way to turn "10-year real

Parameters

querystringrequired: Free text. Matches series titles, notes and tags. Required.
pagenumberoptional: Result page (default 1, upstream stops at 30)
sortenumoptional: Result ordering. Default relevance. Values: relevance, popularity, title, frequency, units, seasonality, updated, start, end.

Request

curl -X GET "https://api.zapi.ink/v1/finance:fred/series-search?query=10-year+real+yield&page=1&sort=popularity" \
  -H "x-api-key: zpi_xxxxxxxxxxxxxxxxxxxxxxxx"

Example response

{
  "page": 1,
  "count": 6,
  "items": [
    {
      "url": "https://fred.stlouisfed.org/series/DFII10",
      "title": "Market Yield on U.S. Treasury Securities at 10-Year Constant Maturity, Quoted on an Investment Basis, Inflation-Indexed",
      "units": "Percent",
      "series": "DFII10",
      "frequency": "Daily",
      "description": "View data of the inflation-adjusted interest rates on 10-year Treasury securities with a constant maturity.",
      "observationEnd": "2026-08-18",
      "observationStart": "2003-01-02",
      "seasonalAdjustment": "Not Seasonally Adjusted"
    },
    {
      "url": "https://fred.stlouisfed.org/series/DFII5",
      "title": "Market Yield on U.S. Treasury Securities at 5-Year Constant Maturity, Quoted on an Investment Basis, Inflation-Indexed",
      "units": "Percent",
      "series": "DFII5",
      "frequency": "Daily",
      "description": "H.15 Statistical Release notes (https://www.federalreserve.gov/releases/h15/default.htm) and the Treasury Yield Curve Methodology (https://home.treasury.gov/policy-issues/financing…",
      "observationEnd": "2026-08-18",
      "observationStart": "2003-01-02",
      "seasonalAdjustment": "Not Seasonally Adjusted"
    },
    {
      "url": "https://fred.stlouisfed.org/series/DFII30",
      "title": "Market Yield on U.S. Treasury Securities at 30-Year Constant Maturity, Quoted on an Investment Basis, Inflation-Indexed",
      "units": "Percent",
      "series": "DFII30",
      "frequency": "Daily",
      "description": "H.15 Statistical Release notes (https://www.federalreserve.gov/releases/h15/default.htm) and the Treasury Yield Curve Methodology (https://home.treasury.gov/policy-issues/financing…",
      "observationEnd": "2026-08-18",
      "observationStart": "2010-02-22",
      "seasonalAdjustment": "Not Seasonally Adjusted"
    }
  ],
  "query": "real yield",
  "total": null,
  "dataset": "series-search",
  "hasMore": false,
  "nextPage": null,
  "provider": "fred"
}

GET

Series/v1/finance:fred/series

1 param

Metadata for one FRED series — units, frequency, seasonal adjustment, the

Parameters

seriesstringoptional: One FRED series id. Case-insensitive. Default DGS10.

Request

curl -X GET "https://api.zapi.ink/v1/finance:fred/series?series=DGS10" \
  -H "x-api-key: zpi_xxxxxxxxxxxxxxxxxxxxxxxx"

Example response

{
  "url": "https://fred.stlouisfed.org/series/DFII10",
  "notes": "For further information regarding treasury constant maturity data, please refer to the H.15 Statistical Release notes and the Treasury Yield Curve Methodology . For questions on the data, please contact the data source . For questions on FRED functionality, please contact us here .",
  "title": "Market Yield on U.S. Treasury Securities at 10-Year Constant Maturity, Quoted on an Investment Basis, Inflation-Indexed",
  "units": "Percent",
  "series": "DFII10",
  "source": "Board of Governors of the Federal Reserve System (US)",
  "dataset": "series",
  "license": "https://fred.stlouisfed.org/legal/#copyright-public-domain",
  "release": {
    "name": "H.15 Selected Interest Rates",
    "releaseId": 18
  },
  "keywords": [
    "tips",
    "10-year",
    "maturity",
    "h15",
    "treasury",
    "securities"
  ],
  "provider": "fred",
  "frequency": "Daily",
  "copyrighted": false,
  "description": "View data of the inflation-adjusted interest rates on 10-year Treasury securities with a constant maturity.",
  "lastUpdated": "2026-08-19T15:16:00-05:00",
  "categoryPath": [
    {
      "name": "Money, Banking, & Finance",
      "categoryId": 32991
    },
    {
      "name": "Interest Rates",
      "categoryId": 22
    },
    {
      "name": "Treasury Inflation-Indexed Securities",
      "categoryId": 82
    },
    {
      "name": "Treasury Constant Maturity",
      "categoryId": 115
    }
  ],
  "nextReleaseDate": "2026-08-20",
  "seasonalAdjustment": "Not Seasonally Adjusted",
  "lastObservationDate": "2026-08-18",
  "lastObservationValue": 2.41,
  "lastObservationPeriod": "2026-08-18"
}

GET

Sources/v1/finance:fred/sources

2 params

The publishers behind the catalogue — statistical agencies, central banks and

Parameters

pagenumberoptional: Catalogue page, 50 sources each (default 1)
querystringoptional: Keep only sources whose name contains this text.

Request

curl -X GET "https://api.zapi.ink/v1/finance:fred/sources?page=1&query=federal+reserve" \
  -H "x-api-key: zpi_xxxxxxxxxxxxxxxxxxxxxxxx"

Example response

{
  "page": 1,
  "count": 12,
  "items": [
    {
      "url": "https://fred.stlouisfed.org/source?soid=1",
      "name": "Board of Governors of the Federal Reserve System (US)",
      "sourceId": 1
    },
    {
      "url": "https://fred.stlouisfed.org/source?soid=91",
      "name": "Federal Reserve Bank of Atlanta",
      "sourceId": 91
    },
    {
      "url": "https://fred.stlouisfed.org/source?soid=54",
      "name": "Federal Reserve Bank of Chicago",
      "sourceId": 54
    },
    {
      "url": "https://fred.stlouisfed.org/source?soid=90",
      "name": "Federal Reserve Bank of Cleveland",
      "sourceId": 90
    },
    {
      "url": "https://fred.stlouisfed.org/source?soid=89",
      "name": "Federal Reserve Bank of Dallas",
      "sourceId": 89
    },
    {
      "url": "https://fred.stlouisfed.org/source?soid=46",
      "name": "Federal Reserve Bank of Kansas City",
      "sourceId": 46
    }
  ],
  "query": "federal reserve",
  "total": null,
  "dataset": "sources",
  "hasMore": false,
  "nextPage": null,
  "provider": "fred"
}

GET

Tags/v1/finance:fred/tags

1 param

The tag vocabulary FRED indexes its catalogue with — geography, frequency,

Parameters

pagenumberoptional: Tag page, ~50 tags each, most-used first (default 1)

Request

curl -X GET "https://api.zapi.ink/v1/finance:fred/tags?page=1" \
  -H "x-api-key: zpi_xxxxxxxxxxxxxxxxxxxxxxxx"

Example response

{
  "page": 1,
  "count": 50,
  "items": [
    {
      "tag": "nsa",
      "name": "Not Seasonally Adjusted",
      "seriesCount": 670000,
      "seriesCountApproximate": true
    },
    {
      "tag": "usa",
      "name": "United States of America",
      "seriesCount": 600000,
      "seriesCountApproximate": true
    },
    {
      "tag": "public domain: citation requested",
      "name": "Public Domain: Citation Requested",
      "seriesCount": 550000,
      "seriesCountApproximate": true
    },
    {
      "tag": "annual",
      "name": "Annual",
      "seriesCount": 440000,
      "seriesCountApproximate": true
    },
    {
      "tag": "county",
      "name": "County or County Equivalent",
      "seriesCount": 290000,
      "seriesCountApproximate": true
    },
    {
      "tag": "nation",
      "name": "Nation",
      "seriesCount": 250000,
      "seriesCountApproximate": true
    }
  ],
  "total": null,
  "dataset": "tags",
  "hasMore": true,
  "nextPage": 2,
  "provider": "fred"
}

GET

Vintage Dates/v1/finance:fred/vintage-dates

2 params

Every vintage ALFRED holds for one series — the dates on which that series was

Parameters

seriesstringoptional: One FRED/ALFRED series id. Case-insensitive. Default GDP.
lengthnumberoptional: Vintage dates to return, newest first (default 50, max 2000)

Request

curl -X GET "https://api.zapi.ink/v1/finance:fred/vintage-dates?series=GDP&length=50" \
  -H "x-api-key: zpi_xxxxxxxxxxxxxxxxxxxxxxxx"

Example response

{
  "count": 50,
  "items": [
    "2026-07-30",
    "2026-06-25",
    "2026-05-28",
    "2026-04-30",
    "2026-04-09",
    "2026-03-13"
  ],
  "total": 413,
  "series": "GDP",
  "dataset": "vintage-dates",
  "provider": "fred",
  "firstVintage": "1991-12-04",
  "latestVintage": "2026-07-30"
}

{ "page": 1, "count": 50, "items": [ { "url": "https://fred.stlouisfed.org/series/DGS10", "title": "Market Yield on U.S. Treasury Securities at 10-Year Constant Maturity, Quoted on an Investment Basis", "units": "Percent", "series": "DGS10", "frequency": "Daily", "observationEnd": "2026-08-18", "observationStart": "1962-01-02", "seasonalAdjustment": "Not Seasonally Adjusted" }, { "url": "https://fred.stlouisfed.org/series/GS10", "title": "Market Yield on U.S. Treasury Securities at 10-Year Constant Maturity, Quoted on an Investment Basis", "units": "Percent", "series": "GS10", "frequency": "Monthly", "observationEnd": "Jul 2026", "observationStart": "Apr 1953", "seasonalAdjustment": "Not Seasonally Adjusted" }, { "url": "https://fred.stlouisfed.org/series/WGS10YR", "title": "Market Yield on U.S. Treasury Securities at 10-Year Constant Maturity, Quoted on an Investment Basis", "units": "Percent", "series": "WGS10YR", "frequency": "Weekly", "observationEnd": "2026-08-14", "observationStart": "1962-01-05", "seasonalAdjustment": "Not Seasonally Adjusted" } ], "total": null, "dataset": "category", "hasMore": true, "category": 115, "children": [ { "name": "Money, Banking, & Finance", "categoryId": 32991 }, { "name": "Interest Rates", "categoryId": 22 } ], "nextPage": 2, "provider": "fred" }

// npm i zpi-sdk import { ZpiClient } from "zpi-sdk"; const client = new ZpiClient({ apiKey: "zpi_xxxxxxxxxxxxxxxxxxxxxxxx" }); const data = await client.run("finance:fred", "category", { "category": 115, "page": 1 }); console.log(data);

curl -X GET "https://api.zapi.ink/v1/finance:fred/observations-vintage?series=GDP&vintages=2020-01-30%2C2020-04-29%2C2026-07-30&from=2019-07-01&to=2019-12-31&length=100" \ -H "x-api-key: zpi_xxxxxxxxxxxxxxxxxxxxxxxx"

{ "to": "2019-12-31", "from": "2019-07-01", "count": 2, "items": [ { "date": "2019-10-01", "values": { "GDP": 21933.217 } }, { "date": "2019-07-01", "values": { "GDP": 21717.171 } } ], "total": 2, "series": [ "GDP" ], "columns": [ { "key": "GDP", "column": "GDP_20260820", "series": "GDP" } ], "dataset": "observations-vintage", "missing": [], "provider": "fred", "vintages": [] }

{ "to": "2026-08-21", "from": "2026-08-17", "page": 1, "year": 2026, "count": 50, "items": [ { "url": "https://fred.stlouisfed.org/release?rid=18", "date": "2026-01-02", "name": "H.15 Selected Interest Rates", "time": "3:15 pm", "released": true, "releaseId": 18 }, { "url": "https://fred.stlouisfed.org/release?rid=18", "date": "2026-01-05", "name": "H.15 Selected Interest Rates", "time": "3:15 pm", "released": true, "releaseId": 18 }, { "url": "https://fred.stlouisfed.org/release?rid=18", "date": "2026-01-06", "name": "H.15 Selected Interest Rates", "time": "3:15 pm", "released": true, "releaseId": 18 }, { "url": "https://fred.stlouisfed.org/release?rid=18", "date": "2026-01-07", "name": "H.15 Selected Interest Rates", "time": "3:15 pm", "released": true, "releaseId": 18 }, { "url": "https://fred.stlouisfed.org/release?rid=18", "date": "2026-01-08", "name": "H.15 Selected Interest Rates", "time": "3:15 pm", "released": true, "releaseId": 18 }, { "url": "https://fred.stlouisfed.org/release?rid=18", "date": "2026-01-09", "name": "H.15 Selected Interest Rates", "time": "3:15 pm", "released": true, "releaseId": 18 } ], "total": null, "dataset": "release-dates", "hasMore": true, "release": 18, "nextPage": 2, "provider": "fred" }

{ "page": 1, "count": 4, "items": [ { "url": "https://fred.stlouisfed.org/release?rid=131", "name": "G.13 Selected Interest Rates", "releaseId": 131 }, { "url": "https://fred.stlouisfed.org/release?rid=18", "name": "H.15 Selected Interest Rates", "releaseId": 18 }, { "url": "https://fred.stlouisfed.org/release?rid=484", "name": "Key ECB Interest Rates", "releaseId": 484 }, { "url": "https://fred.stlouisfed.org/release?rid=94", "name": "Survey of Secondary Market Prices and Yields, and Interest Rates for Home Loans", "releaseId": 94 } ], "query": "interest rates", "total": null, "dataset": "releases", "hasMore": false, "nextPage": null, "provider": "fred" }

curl -X GET "https://api.zapi.ink/v1/finance:fred/series-observations?series=DGS10%2CDGS2%2CT10Y2Y&from=2026-01-01&to=2026-08-18&transformation=pc1&frequency=Monthly&aggregation=avg&length=100" \ -H "x-api-key: zpi_xxxxxxxxxxxxxxxxxxxxxxxx"

{ "to": "2026-08-01", "from": "2024-01-01", "count": 100, "items": [ { "date": "2026-07-31", "values": { "DFII10": 2.47 } }, { "date": "2026-07-30", "values": { "DFII10": 2.41 } }, { "date": "2026-07-29", "values": { "DFII10": 2.41 } }, { "date": "2026-07-28", "values": { "DFII10": 2.41 } }, { "date": "2026-07-27", "values": { "DFII10": 2.44 } }, { "date": "2026-07-24", "values": { "DFII10": 2.43 } } ], "total": 674, "series": [ "DFII10" ], "dataset": "series-observations", "missing": [], "provider": "fred", "resolved": [ "DFII10" ], "transformation": "lin" }

{ "page": 1, "count": 6, "items": [ { "url": "https://fred.stlouisfed.org/series/DFII10", "title": "Market Yield on U.S. Treasury Securities at 10-Year Constant Maturity, Quoted on an Investment Basis, Inflation-Indexed", "units": "Percent", "series": "DFII10", "frequency": "Daily", "description": "View data of the inflation-adjusted interest rates on 10-year Treasury securities with a constant maturity.", "observationEnd": "2026-08-18", "observationStart": "2003-01-02", "seasonalAdjustment": "Not Seasonally Adjusted" }, { "url": "https://fred.stlouisfed.org/series/DFII5", "title": "Market Yield on U.S. Treasury Securities at 5-Year Constant Maturity, Quoted on an Investment Basis, Inflation-Indexed", "units": "Percent", "series": "DFII5", "frequency": "Daily", "description": "H.15 Statistical Release notes (https://www.federalreserve.gov/releases/h15/default.htm) and the Treasury Yield Curve Methodology (https://home.treasury.gov/policy-issues/financing…", "observationEnd": "2026-08-18", "observationStart": "2003-01-02", "seasonalAdjustment": "Not Seasonally Adjusted" }, { "url": "https://fred.stlouisfed.org/series/DFII30", "title": "Market Yield on U.S. Treasury Securities at 30-Year Constant Maturity, Quoted on an Investment Basis, Inflation-Indexed", "units": "Percent", "series": "DFII30", "frequency": "Daily", "description": "H.15 Statistical Release notes (https://www.federalreserve.gov/releases/h15/default.htm) and the Treasury Yield Curve Methodology (https://home.treasury.gov/policy-issues/financing…", "observationEnd": "2026-08-18", "observationStart": "2010-02-22", "seasonalAdjustment": "Not Seasonally Adjusted" } ], "query": "real yield", "total": null, "dataset": "series-search", "hasMore": false, "nextPage": null, "provider": "fred" }

{ "url": "https://fred.stlouisfed.org/series/DFII10", "notes": "For further information regarding treasury constant maturity data, please refer to the H.15 Statistical Release notes and the Treasury Yield Curve Methodology . For questions on the data, please contact the data source . For questions on FRED functionality, please contact us here .", "title": "Market Yield on U.S. Treasury Securities at 10-Year Constant Maturity, Quoted on an Investment Basis, Inflation-Indexed", "units": "Percent", "series": "DFII10", "source": "Board of Governors of the Federal Reserve System (US)", "dataset": "series", "license": "https://fred.stlouisfed.org/legal/#copyright-public-domain", "release": { "name": "H.15 Selected Interest Rates", "releaseId": 18 }, "keywords": [ "tips", "10-year", "maturity", "h15", "treasury", "securities" ], "provider": "fred", "frequency": "Daily", "copyrighted": false, "description": "View data of the inflation-adjusted interest rates on 10-year Treasury securities with a constant maturity.", "lastUpdated": "2026-08-19T15:16:00-05:00", "categoryPath": [ { "name": "Money, Banking, & Finance", "categoryId": 32991 }, { "name": "Interest Rates", "categoryId": 22 }, { "name": "Treasury Inflation-Indexed Securities", "categoryId": 82 }, { "name": "Treasury Constant Maturity", "categoryId": 115 } ], "nextReleaseDate": "2026-08-20", "seasonalAdjustment": "Not Seasonally Adjusted", "lastObservationDate": "2026-08-18", "lastObservationValue": 2.41, "lastObservationPeriod": "2026-08-18" }

{ "page": 1, "count": 12, "items": [ { "url": "https://fred.stlouisfed.org/source?soid=1", "name": "Board of Governors of the Federal Reserve System (US)", "sourceId": 1 }, { "url": "https://fred.stlouisfed.org/source?soid=91", "name": "Federal Reserve Bank of Atlanta", "sourceId": 91 }, { "url": "https://fred.stlouisfed.org/source?soid=54", "name": "Federal Reserve Bank of Chicago", "sourceId": 54 }, { "url": "https://fred.stlouisfed.org/source?soid=90", "name": "Federal Reserve Bank of Cleveland", "sourceId": 90 }, { "url": "https://fred.stlouisfed.org/source?soid=89", "name": "Federal Reserve Bank of Dallas", "sourceId": 89 }, { "url": "https://fred.stlouisfed.org/source?soid=46", "name": "Federal Reserve Bank of Kansas City", "sourceId": 46 } ], "query": "federal reserve", "total": null, "dataset": "sources", "hasMore": false, "nextPage": null, "provider": "fred" }

{ "page": 1, "count": 50, "items": [ { "tag": "nsa", "name": "Not Seasonally Adjusted", "seriesCount": 670000, "seriesCountApproximate": true }, { "tag": "usa", "name": "United States of America", "seriesCount": 600000, "seriesCountApproximate": true }, { "tag": "public domain: citation requested", "name": "Public Domain: Citation Requested", "seriesCount": 550000, "seriesCountApproximate": true }, { "tag": "annual", "name": "Annual", "seriesCount": 440000, "seriesCountApproximate": true }, { "tag": "county", "name": "County or County Equivalent", "seriesCount": 290000, "seriesCountApproximate": true }, { "tag": "nation", "name": "Nation", "seriesCount": 250000, "seriesCountApproximate": true } ], "total": null, "dataset": "tags", "hasMore": true, "nextPage": 2, "provider": "fred" }

{ "count": 50, "items": [ "2026-07-30", "2026-06-25", "2026-05-28", "2026-04-30", "2026-04-09", "2026-03-13" ], "total": 413, "series": "GDP", "dataset": "vintage-dates", "provider": "fred", "firstVintage": "1991-12-04", "latestVintage": "2026-07-30" }

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