U.S. Treasury Fiscal Data Interest Rates API

openapi: 3.0.3
info:
  title: U.S. Treasury Fiscal Data Daily Treasury Statement Interest Rates API
  description: 'The U.S. Treasury Fiscal Data API is a free, public, read-only RESTful API from the Bureau of the Fiscal Service that serves federal government financial data - the national debt, average interest rates on Treasury securities, daily and monthly Treasury statements of revenue and spending, Treasury reporting rates of exchange, and Treasury securities auctions.


    The API accepts only GET requests, returns JSON by default (CSV and XML are available via the `format` parameter), and uses standard HTTP response codes. No registration, API key, or authentication is required and the data is in the public domain.


    Each endpoint maps to a single database table from a published report (a "dataset"). Every endpoint accepts the same query parameters - `fields` for column selection, `filter` for row filtering, `sort` for ordering, `format` for the response type, and `page[number]` / `page[size]` for pagination. Endpoints are versioned individually as `v1` or `v2`; consult each dataset''s detail page for its current version.


    This document models a representative set of the most-requested endpoints. The full catalog of datasets is listed at https://fiscaldata.treasury.gov/api-documentation/.'
  version: '1.0'
  contact:
    name: U.S. Treasury Fiscal Data
    url: https://fiscaldata.treasury.gov
  license:
    name: Public Domain (U.S. Government Work)
    url: https://fiscaldata.treasury.gov/about-us/
servers:
- url: https://api.fiscaldata.treasury.gov/services/api/fiscal_service
  description: Fiscal Data production API (no authentication required)
tags:
- name: Interest Rates
  description: Average interest rates on U.S. Treasury securities.
paths:
  /v2/accounting/od/avg_interest_rates:
    get:
      operationId: getAverageInterestRates
      tags:
      - Interest Rates
      summary: Average Interest Rates on U.S. Treasury Securities
      description: Monthly average interest rate by security type and description - Bills, Notes, Bonds, TIPS, Floating Rate Notes, and government account series. Filter by `security_desc` and `record_date` for rate time series.
      parameters:
      - $ref: '#/components/parameters/Fields'
      - $ref: '#/components/parameters/Filter'
      - $ref: '#/components/parameters/Sort'
      - $ref: '#/components/parameters/Format'
      - $ref: '#/components/parameters/PageNumber'
      - $ref: '#/components/parameters/PageSize'
      responses:
        '200':
          $ref: '#/components/responses/DatasetResponse'
components:
  responses:
    DatasetResponse:
      description: A page of dataset records with metadata and pagination links. When `format=csv` or `format=xml`, the body is CSV or XML instead of JSON.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/DatasetResponse'
        text/csv:
          schema:
            type: string
        application/xml:
          schema:
            type: string
  parameters:
    Sort:
      name: sort
      in: query
      required: false
      description: 'Comma-separated fields to sort by, ascending by default; prefix a field with `-` for descending. Example: `-record_date`.'
      schema:
        type: string
    Format:
      name: format
      in: query
      required: false
      description: Response format. Defaults to JSON.
      schema:
        type: string
        enum:
        - json
        - csv
        - xml
        default: json
    Fields:
      name: fields
      in: query
      required: false
      description: 'Comma-separated list of fields (columns) to return. Omit to return all fields for the dataset. Example: `record_date,tot_pub_debt_out_amt`.'
      schema:
        type: string
    PageNumber:
      name: page[number]
      in: query
      required: false
      description: The page of results to return (1-based).
      schema:
        type: integer
        minimum: 1
        default: 1
    PageSize:
      name: page[size]
      in: query
      required: false
      description: Number of results per page. Maximum 10000.
      schema:
        type: integer
        minimum: 1
        maximum: 10000
        default: 100
    Filter:
      name: filter
      in: query
      required: false
      description: 'Filter rows using `field:operator:value`, comma-separated for multiple filters (AND). Operators are `lt`, `lte`, `gt`, `gte`, `eq`, and `in` (values in parentheses). Example: `record_date:gte:2020-01-01,security_desc:eq:Treasury Bills`.'
      schema:
        type: string
  schemas:
    DatasetResponse:
      type: object
      description: Standard Fiscal Data envelope. `data` is an array of records whose fields vary per dataset; all values are returned as strings.
      properties:
        data:
          type: array
          items:
            type: object
            additionalProperties:
              type: string
        meta:
          $ref: '#/components/schemas/Meta'
        links:
          $ref: '#/components/schemas/Links'
    Links:
      type: object
      description: Pagination links (query-string fragments).
      properties:
        self:
          type: string
        first:
          type: string
        prev:
          type: string
          nullable: true
        next:
          type: string
          nullable: true
        last:
          type: string
    Meta:
      type: object
      description: Metadata describing the returned fields and the full result set.
      properties:
        count:
          type: integer
          description: Number of records on this page.
        labels:
          type: object
          description: Human-readable label for each field.
          additionalProperties:
            type: string
        dataTypes:
          type: object
          description: Data type for each field (e.g. DATE, CURRENCY, INTEGER, STRING).
          additionalProperties:
            type: string
        dataFormats:
          type: object
          description: Display format for each field (e.g. YYYY-MM-DD, $10.20).
          additionalProperties:
            type: string
        total-count:
          type: integer
          description: Total number of records across all pages for the query.
        total-pages:
          type: integer
          description: Total number of pages for the query at the current page size.