The 9:30 a.m. Eastern open, read on three clocks, by month

Name: The 9:30 a.m. Eastern open, read on three clocks, by month
Creator: Strasmore
Published: 2026-11-07
License: https://www.strasmore.com/terms/

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 2026-11-07, from US Stock Market Hours in Mountain Time.

as of 2026-11-07 series 14×6read in context →

The 9:30 a.m. Eastern open, read on three clocks, by month — 14 rows by 6 columns, computed 2026-11-07 from US exchange, SIP and OPRA data.
month	denver_open	phoenix_open_earliest	phoenix_open_latest	denver_gap_hours	phoenix_gap_hours
2025-10	07:30	06:30	06:30	2	3
2025-11	07:30	07:30	07:30	2	2
2025-12	07:30	07:30	07:30	2	2
2026-01	07:30	07:30	07:30	2	2
2026-02	07:30	07:30	07:30	2	2
2026-03	07:30	06:30	07:30	2	2.77
2026-04	07:30	06:30	06:30	2	3
2026-05	07:30	06:30	06:30	2	3
2026-06	07:30	06:30	06:30	2	3
2026-07	07:30	06:30	06:30	2	3
2026-08	07:30	06:30	06:30	2	3
2026-09	07:30	06:30	06:30	2	3
2026-10	07:30	06:30	06:30	2	3
2026-11	07:30	07:30	07:30	2	2

Rows × columns: 14 × 6
Computed: 2026-11-07
Completeness: No missing values
Source: US exchange, SIP and OPRA market data
Licence: Strasmore terms · free, no signup
Formats: JSON · CSV · the SQL below

What each column holds

Column definitions for The 9:30 a.m. Eastern open, read on three clocks, by month, derived from the stored result.
Column	Type	Range
`month`	text	14 distinct values (2025-10, 2025-11, 2025-12…)
`denver_open`	text	1 distinct value (07:30)
`phoenix_open_earliest`	text	2 distinct values (06:30, 07:30)
`phoenix_open_latest`	text	2 distinct values (06:30, 07:30)
`denver_gap_hours`	number	every row is 2
`phoenix_gap_hours`	number	2 to 3

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 2026-11-07, 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.

WITH session_opens AS
(
    SELECT
        toDate(toTimeZone(window_start, 'America/New_York')) AS session_date,
        min(window_start)                                    AS open_utc
    FROM global_markets.delayed_stocks_minute_aggs
    WHERE ticker = 'SPY'
      AND window_start >= today() - 400
      AND window_start <  today() - 2
      AND toHour(toTimeZone(window_start, 'America/New_York'))   = 9
      AND toMinute(toTimeZone(window_start, 'America/New_York')) = 30
    GROUP BY session_date
)
SELECT
    formatDateTime(toStartOfMonth(session_date), '%Y-%m')                 AS month,
    min(formatDateTime(toTimeZone(open_utc, 'America/Denver'),  '%H:%i')) AS denver_open,
    min(formatDateTime(toTimeZone(open_utc, 'America/Phoenix'), '%H:%i')) AS phoenix_open_earliest,
    max(formatDateTime(toTimeZone(open_utc, 'America/Phoenix'), '%H:%i')) AS phoenix_open_latest,
    round(avg(toHour(toTimeZone(open_utc, 'America/New_York'))
              - toHour(toTimeZone(open_utc, 'America/Denver'))), 2)       AS denver_gap_hours,
    round(avg(toHour(toTimeZone(open_utc, 'America/New_York'))
              - toHour(toTimeZone(open_utc, 'America/Phoenix'))), 2)      AS phoenix_gap_hours
FROM session_opens
GROUP BY month
ORDER BY month

SQL to run

WITH session_opens AS
(
    SELECT
        toDate(toTimeZone(window_start, 'America/New_York')) AS session_date,
        min(window_start)                                    AS open_utc
    FROM global_markets.delayed_stocks_minute_aggs
    WHERE ticker = 'SPY'
      AND window_start >= today() - 400
      AND window_start <  today() - 2
      AND toHour(toTimeZone(window_start, 'America/New_York'))   = 9
      AND toMinute(toTimeZone(window_start, 'America/New_York')) = 30
    GROUP BY session_date
)
SELECT
    formatDateTime(toStartOfMonth(session_date), '%Y-%m')                 AS month,
    min(formatDateTime(toTimeZone(open_utc, 'America/Denver'),  '%H:%i')) AS denver_open,
    min(formatDateTime(toTimeZone(open_utc, 'America/Phoenix'), '%H:%i')) AS phoenix_open_earliest,
    max(formatDateTime(toTimeZone(open_utc, 'America/Phoenix'), '%H:%i')) AS phoenix_open_latest,
    round(avg(toHour(toTimeZone(open_utc, 'America/New_York'))
              - toHour(toTimeZone(open_utc, 'America/Denver'))), 2)       AS denver_gap_hours,
    round(avg(toHour(toTimeZone(open_utc, 'America/New_York'))
              - toHour(toTimeZone(open_utc, 'America/Phoenix'))), 2)      AS phoenix_gap_hours
FROM session_opens
GROUP BY month
ORDER BY month

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