Locked-or-crossed records per 10,000 updates by 30-minute ET bucket, checked set, extended hours included
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 2026-08-22, from Locked and Crossed Markets, Explained With Data.
| et_time | locked_or_crossed_per_10k | updates_m |
|---|---|---|
| 04:00 | 14.5 | 0.47 |
| 04:30 | 5.7 | 0.29 |
| 05:00 | 8.4 | 0.32 |
| 05:30 | 8.9 | 0.28 |
| 06:00 | 8.8 | 0.25 |
| 06:30 | 17.6 | 0.26 |
| 07:00 | 38.6 | 0.26 |
| 07:30 | 40.2 | 0.25 |
| 08:00 | 45.5 | 0.42 |
| 08:30 | 21.6 | 0.64 |
| 09:00 | 54.8 | 0.49 |
| 09:30 | 36.9 | 8.66 |
| 10:00 | 42.9 | 6.25 |
| 10:30 | 47.9 | 4.67 |
| 11:00 | 48.3 | 3.98 |
| 11:30 | 46.7 | 3.32 |
| 12:00 | 51.6 | 2.36 |
| 12:30 | 57.8 | 2.01 |
| 13:00 | 64 | 2 |
| 13:30 | 66.6 | 1.83 |
| 14:00 | 63.2 | 1.9 |
| 14:30 | 77.1 | 1.7 |
| 15:00 | 89.4 | 1.92 |
| 15:30 | 103.1 | 3.61 |
| 16:00 | 170.1 | 0.39 |
| 16:30 | 148.1 | 0.13 |
| 17:00 | 76.7 | 0.01 |
| 17:30 | 113.8 | 0.01 |
| 18:00 | 50.2 | 0.08 |
| 18:30 | 27.4 | 0.05 |
| 19:00 | 29 | 0.05 |
| 19:30 | 37.6 | 0.08 |
- Rows × columns
- 32 × 3
- Period covered
- to
- 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 |
|---|---|---|---|
et_time |
date | 04:00 to 19:30 | |
locked_or_crossed_per_10k |
number | 5.7 to 170.1 | |
updates_m |
number | 0.01 to 8.66 |
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.
the exact SQL behind every number
SELECT formatDateTime(toStartOfInterval(toTimeZone(sip_timestamp, 'America/New_York'), INTERVAL 30 MINUTE), '%H:%i') AS et_time,
round(countIf(bid_price >= ask_price AND ask_price > 0 AND bid_price > 0) / toFloat64(count()) * 1e4, 1) AS locked_or_crossed_per_10k,
round(count() / 1e6, 2) AS updates_m
FROM global_markets.cache_stocks_quotes
WHERE ticker IN ('SPY', 'QQQ', 'AAPL', 'NVDA', 'MSFT', 'TSLA', 'KO', 'AMD', 'NATH', 'SENEA')
AND sip_timestamp >= toDateTime(today() - 10)
AND sip_timestamp < toDateTime(today() - 3)
GROUP BY et_time
HAVING et_time >= '04:00' AND et_time < '20:00'
ORDER BY et_time
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