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Query Parameters — U.S. Treasury Fiscal Data API

skills/usfiscaldata/references/parameters.md

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Query Parameters — U.S. Treasury Fiscal Data API

All parameters are optional. Combine them with & in the URL query string.

fields= — Select Columns

Returns only the specified fields. Accepts a comma-separated list of field names.

?fields=record_date,tot_pub_debt_out_amt
?fields=country_currency_desc,exchange_rate,record_date
  • If omitted, all fields are returned
  • Invalid field names cause an error
  • Omitting some fields can trigger automatic aggregation (see below)

Aggregation / Auto-Sum

When the fields= parameter excludes some non-numeric fields, the API automatically groups by the remaining fields and sums numeric values.

python
# Returns sum of transaction amounts grouped by record_date and transaction_type
params = {
    "fields": "record_date,transaction_type,transaction_today_amt"
}

filter= — Filter Records

Narrow results by field values. Multiple field filters are comma-separated in a single filter= parameter.

Filter Syntax

filter=<field>:<operator>:<value>
filter=<field>:<operator>:<value>,<field>:<operator>:<value>

Operators

OperatorMeaningExample
eqEqual tofilter=record_date:eq:2024-03-31
ltLess thanfilter=exchange_rate:lt:1.5
lteLess than or equalfilter=record_date:lte:2024-12-31
gtGreater thanfilter=record_fiscal_year:gt:2010
gteGreater than or equalfilter=record_date:gte:2024-01-01
inContained in setfilter=country_currency_desc:in:(Canada-Dollar,Mexico-Peso)

Date Filters

Use YYYY-MM-DD format for dates:

filter=record_date:gte:2024-01-01
filter=record_date:gte:2023-01-01,record_date:lte:2023-12-31

Multi-Field Filters

filter=country_currency_desc:in:(Canada-Dollar,Mexico-Peso),record_date:gte:2024-01-01

Common Filter Fields

Most endpoints have these standard date fields:

  • record_date — The date of the record (YYYY-MM-DD)
  • record_fiscal_year — Fiscal year (e.g., 2024)
  • record_fiscal_quarter — Fiscal quarter (1-4)
  • record_calendar_year — Calendar year
  • record_calendar_month — Calendar month (01-12)

sort= — Sort Results

Sort by one or more fields. Prefix - for descending order.

?sort=-record_date           # Most recent first
?sort=record_date            # Oldest first
?sort=-record_fiscal_year,-record_fiscal_quarter  # Nested sort

Default: Sorted by the first column (usually record_date ascending).

format= — Output Format

?format=json    # Default
?format=csv     # Comma-separated values
?format=xml     # XML

When using CSV or XML format, the response is the raw file content rather than JSON.

page[size]= and page[number]= — Pagination

Controls how many records per page and which page to return.

?page[size]=100&page[number]=1    # Default (100 records, page 1)
?page[size]=10000                  # Large page to reduce requests
?page[number]=5&page[size]=50     # 50 records starting at page 5
  • Default page size: 100
  • Default page number: 1
  • Use meta.total-pages in the response to know how many pages exist
  • Use meta.total-count for total record count

Fetch All Records

For small result sets where meta.total-pages is 1, a single request with page[size]=10000 is enough. Use fetch_all() below when pagination is required.

python
import time
import requests
import pandas as pd

def fetch_all(endpoint, params=None, max_pages=50, max_records=500_000):
    """Fetch paginated results and return as DataFrame.

    Stops when all pages are retrieved or when max_pages / max_records limits
    are reached. Retries on HTTP 429 with exponential backoff.
    """
    params = dict(params or {})
    params["page[size]"] = min(params.get("page[size]", 10000), 10000)
    params["page[number]"] = 1

    base = "https://api.fiscaldata.treasury.gov/services/api/fiscal_service"
    all_data = []

    for _ in range(max_pages):
        for attempt in range(3):
            resp = requests.get(f"{base}{endpoint}", params=params)
            if resp.status_code == 429:
                time.sleep(2 ** attempt)
                continue
            resp.raise_for_status()
            break
        else:
            raise RuntimeError("Rate limited after retries")

        result = resp.json()
        if "error" in result:
            raise ValueError(f"API error: {result['error']} — {result.get('message', '')}")

        all_data.extend(result["data"])
        if len(all_data) >= max_records:
            all_data = all_data[:max_records]
            break

        meta = result["meta"]
        if params["page[number]"] >= meta["total-pages"]:
            break
        params["page[number]"] += 1
        time.sleep(0.1)
    else:
        raise RuntimeError(
            f"Reached max_pages={max_pages}; increase limit or narrow filters"
        )

    return pd.DataFrame(all_data)

Combining Parameters

python
params = {
    "fields": "country_currency_desc,exchange_rate,record_date",
    "filter": "country_currency_desc:in:(Canada-Dollar,Euro),record_date:gte:2020-01-01",
    "sort": "-record_date",
    "format": "json",
    "page[size]": 100,
    "page[number]": 1
}
resp = requests.get(
    "https://api.fiscaldata.treasury.gov/services/api/fiscal_service/v1/accounting/od/rates_of_exchange",
    params=params
)