---
title: "H.4.1 - Factors Affecting Reserve Balances (headline)"
method: GET
path: "/api/v1/fed/h41"
tags: ["Central Banks & Monetary"]
---

# H.4.1 - Factors Affecting Reserve Balances (headline)

`GET /api/v1/fed/h41`

Federal Reserve H.4.1 statistical release (weekly Wednesday/Thursday). Headline balance-sheet lines: assets (Treasuries, MBS, agency, loans, liquidity swaps), liabilities (reverse repo, Treasury general account, currency, foreign deposits), and capital. Subset of the full H.4.1 (hundreds of granular lines). Data drawn live from FRED with 1-hour cache.

## Query parameters

- `lookback_weeks` integer — Weeks of history to return (default 52, max 260).
- `include_discontinued` boolean — When true, include discontinued and superseded series in the response. Default false returns only release_status=active series.

## Response `200`

H.4.1 weekly observation grid with series_metadata + failed_series envelope.

- EnvelopeFedH3Data
  - `data` FedH3Data, required
    - `release_date` string, nullable — FRED release publish date if known, otherwise null. The B3 endpoints currently leave this null and use latest_observation_date for freshness.
    - `latest_observation_date` string, nullable — Max observation_date across active series.
    - `series_metadata` FedReleaseSeriesMetadata[], required
      - `series_id` string, required
      - `title` string, required
      - `units` string, required
      - `frequency` string, required
      - `seasonally_adjusted` boolean, required
      - `release_status` string, required — One of: active, discontinued, superseded.
      - `last_updated` string, nullable — ISO 8601 timestamp from FRED metadata. Null when not retrieved.
      - `last_observation_date` string, nullable — Latest observation date for this series, ISO 8601.
      - `superseded_by` string, nullable — Replacement series ID when release_status=superseded.
    - `failed_series` string[] — Series whose fetch failed (network, 404, parse error). Distinct from legitimate null observations inside snapshots. Empty list = full success.
    - `weekly_data` FedReleaseSnapshot[], required
      - `observation_date` string, required
      - `series` object, required — Map series_id -> numeric value or null.
  - `meta` SugraMeta, required — Metadata attached to every /api/v1/* response envelope.
    - `endpoint` string, required — Requested endpoint path.
    - `data_time` string, required — ISO 8601 UTC timestamp of the source data, not of the request.
    - `response_time` string, required — ISO 8601 UTC timestamp when this response was produced.
    - `provider` string, required — API name and version.
    - `source` string, nullable — Identifier of the primary upstream source used for this response.
    - `attribution` string, nullable — Human-readable attribution mandated by an upstream source (e.g. a securities regulator or self-regulatory organization). Present only on responses whose source requires the owner and source to be clearly identified. Do not remove or alter it when using the response.
    - `fallback_used` boolean, nullable — True when the primary source failed and a fallback produced the data.
    - `fallback_chain` string[], nullable — Ordered list of sources attempted, in the order they were tried.
    - `cached` boolean, nullable — True when this response was served from the internal cache.
    - `stale` boolean, nullable — True when the cached response was returned after the upstream rate-limited or errored. Clients can use this to detect degraded data.

## Other responses

- `401` — Missing or invalid `x-api-key` header.
- `422` — Validation Error
- `429` — Daily rate limit exceeded. Check `X-RateLimit-Reset` for the next window.
- `503` — Upstream source is temporarily unavailable. Retry after a short delay.

---

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