Extract revenue and net income history from 10-K XBRL

Build a multi-year revenue, net income and margin table for one company from XBRL facts, handling revenue tag changes and repeated prior-year values.

Every 10-K and 10-Q includes XBRL: each number in the financial statements tagged with a concept, a period and a unit. /v1/xbrl/company-concept returns every value a company has reported for one concept, across all its filings. This tutorial turns those facts into a clean annual table of revenue, net income and margin.

Two things to handle

1. Repeated values. Each 10-K reports the current year and prior years, so the same fiscal year appears in several filings. Keep one value per period end; this script takes the most recently filed one, which reflects any revision.
2. Changing tags. Since revenue recognition rules changed in 2018, many companies report revenue as RevenueFromContractWithCustomerExcludingAssessedTax instead of Revenues, and some switch back and forth. Read both and merge.

Annual values are the facts from a 10-K whose period runs about a year (350 to 380 days, which allows for 53 week fiscal years). Quarterly facts from 10-Qs and year to date facts are dropped.

The code

import os
from datetime import date

import requests

BASE = "https://secfeedapi.com"
HEADERS = {"Authorization": f"Bearer {os.environ['SECFEED_KEY']}"}


def concept(ticker, tag):
    r = requests.get(f"{BASE}/v1/xbrl/company-concept", params={"ticker": ticker, "concept": tag}, headers=HEADERS, timeout=120)
    if r.status_code == 404:
        return []
    r.raise_for_status()
    return r.json()["units"].get("USD", [])


def annual(facts):
    """One value per fiscal year: full-year facts from 10-Ks, latest filing wins (each 10-K repeats prior years)."""
    out = {}
    for f in facts:
        days = (date.fromisoformat(f["end"]) - date.fromisoformat(f["start"])).days if f.get("start") else 0
        if f["form"] in ("10-K", "10-K/A") and 350 <= days <= 380:
            if f["end"] not in out or f["filed"] > out[f["end"]]["filed"]:
                out[f["end"]] = f
    return out


ticker = "COST"
# companies switch revenue tags over time, so read both and keep the most recently filed value per year
revenue = annual(concept(ticker, "Revenues") + concept(ticker, "RevenueFromContractWithCustomerExcludingAssessedTax"))
net = annual(concept(ticker, "NetIncomeLoss"))

print(f"{ticker} annual results from XBRL (USD millions)")
print(f"{'Fiscal year end':16}{'Revenue':>12}{'Net income':>13}{'Margin':>9}  Source 10-K filed")
for end in sorted(revenue)[-8:]:
    rev, ni = revenue[end]["val"], net.get(end, {}).get("val")
    margin = f"{ni / rev:.2%}" if ni else ""
    print(f"{end:16}{rev / 1e6:>12,.0f}{(ni or 0) / 1e6:>13,.0f}{margin:>9}  {revenue[end]['filed']}")

Output

Run on 2026-10-13 for Costco (fiscal years end around the start of September).

COST annual results from XBRL (USD millions)
Fiscal year end      Revenue   Net income   Margin  Source 10-K filed
2019-09-01           152,703        3,659    2.40%  2021-10-06
2020-08-30           166,761        4,002    2.40%  2022-10-05
2021-08-29           195,929        5,007    2.56%  2023-10-11
2022-08-28           226,954        5,844    2.57%  2024-10-09
2023-09-03           242,290        6,292    2.60%  2025-10-08
2024-09-01           254,453        7,367    2.90%  2026-10-07
2025-08-31           275,235        8,099    2.94%  2026-10-07
2026-08-30           303,154        9,226    3.04%  2026-10-07
200 25 22.6
225 25 21.1

Reading the result

• Costco's fiscal year ending 2023-09-03 had 53 weeks, which the 350 to 380 day window keeps.
• The source column shows which 10-K supplied each value. Years reported again in a later 10-K take the later filing.
• Margin here is net income over revenue. Swap in OperatingIncomeLoss or GrossProfit for other margins, checking the company uses that tag.

Variations

• Several companies: loop over tickers. To compare one concept across all companies for one period, use /v1/xbrl/frames (see Compare companies with frames).
• Quarterly: keep 10-Q facts with a period of about 90 days.
• Full statements: /v1/financial-statements returns the income statement, balance sheet and cash flow for the latest filings without choosing tags.

Next steps

• XBRL-to-JSON Converter
• Financial Statements API
• Form 10-K dataset
• API reference