dst_windows
Answered against 22 years of US equities and 12 years of US options data and published with the query that produced it. This result is stored as of 2026-09-20, from us-stock-market-hours-london-time.
| label | begins | ends | days_at_four_hours | regular_session_london |
|---|---|---|---|---|
| Spring 2026 | Mar 8 | Mar 28 | 21 | 13:30 to 20:00 |
| Autumn 2026 | Oct 25 | Oct 31 | 7 | 13:30 to 20:00 |
| Spring 2027 | Mar 14 | Mar 27 | 14 | 13:30 to 20:00 |
| Autumn 2027 | Oct 31 | Nov 6 | 7 | 13:30 to 20:00 |
- Rows × columns
- 4 × 5
- Computed
- Completeness
- No missing values
- Source
- US exchange, SIP and OPRA market data
- Licence
- Strasmore terms · free, no signup
What each column holds
| Column | Type | Range | Notes |
|---|---|---|---|
label |
text | 4 distinct values (Autumn 2026, Autumn 2027, Spring 2026…) | |
begins |
text | 4 distinct values (Mar 14, Mar 8, Oct 25…) | |
ends |
text | 4 distinct values (Mar 27, Mar 28, Nov 6…) | |
days_at_four_hours |
number | 7 to 21 | |
regular_session_london |
text | 1 distinct value (13:30 to 20:00) |
Computed from Strasmore's warehouse of US exchange, SIP and OPRA market data. Equity prices are delayed; options greeks and implied volatility are end-of-day. This result is stored, not recomputed on load — it is exactly the numbers that were returned on , and the query below is what returned them.
Run it yourself
This is the exact query behind the result above. Change a ticker, a date or a column and run it against the warehouse — no account, no key. The no-signup tier is smaller than the one this page was computed on; a query that reaches past it comes back saying which plan runs it.
SELECT
concat(if(toMonth(min(day)) < 7, 'Spring ', 'Autumn '), toString(toYear(min(day)))) AS label,
concat(formatDateTime(min(day), '%b'), ' ', toString(toDayOfMonth(min(day)))) AS begins,
concat(formatDateTime(max(day), '%b'), ' ', toString(toDayOfMonth(max(day)))) AS ends,
count() AS days_at_four_hours,
concat(any(open_london), ' to ', any(close_london)) AS regular_session_london
FROM
(
SELECT
day,
formatDateTime(toTimeZone(toDateTime(concat(toString(day), ' 09:30:00'), 'America/New_York'), 'Europe/London'), '%H:%i') AS open_london,
formatDateTime(toTimeZone(toDateTime(concat(toString(day), ' 16:00:00'), 'America/New_York'), 'Europe/London'), '%H:%i') AS close_london
FROM
(
SELECT toDate('2026-01-01') + arrayJoin(range(730)) AS day
)
)
WHERE open_london = '13:30'
GROUP BY toYear(day), toMonth(day) < 7
ORDER BY min(day)