STRASMORE/EXPLORE 2,170 QUERIES

Stocks NBBO update count: July 28 vs July 27, with named-ticker updates (millions)

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 2026-08-01, from Market Recap: July 28, 2026, The Day in Numbers.

as of scalar 1×6read in context →
jul28 updates m
536.07
jul27 updates m
553.53
day over day pct
-3.2
jul28 spy updates m
4.72
jul28 qqq updates m
5.94
jul28 nvda updates m
3.01
Rows × columns
1 × 6
Computed
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 Stocks NBBO update count: July 28 vs July 27, with named-ticker updates (millions), derived from the stored result.
ColumnTypeRangeNotes
jul28_updates_m number every row is 536.07
jul27_updates_m number every row is 553.53
day_over_day_pct number every row is -3.2 percent
jul28_spy_updates_m number every row is 4.72
jul28_qqq_updates_m number every row is 5.94
jul28_nvda_updates_m number every row is 3.01

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
    round(countIf(toDate(sip_timestamp) = toDate('2026-07-28')) / 1e6, 2) AS jul28_updates_m,
    round(countIf(toDate(sip_timestamp) = toDate('2026-07-27')) / 1e6, 2) AS jul27_updates_m,
    round((countIf(toDate(sip_timestamp) = toDate('2026-07-28')) / countIf(toDate(sip_timestamp) = toDate('2026-07-27')) - 1) * 100, 1) AS day_over_day_pct,
    round(countIf(toDate(sip_timestamp) = toDate('2026-07-28') AND ticker = 'SPY') / 1e6, 2) AS jul28_spy_updates_m,
    round(countIf(toDate(sip_timestamp) = toDate('2026-07-28') AND ticker = 'QQQ') / 1e6, 2) AS jul28_qqq_updates_m,
    round(countIf(toDate(sip_timestamp) = toDate('2026-07-28') AND ticker = 'NVDA') / 1e6, 2) AS jul28_nvda_updates_m
FROM global_markets.cache_stocks_quotes
WHERE sip_timestamp >= '2026-07-27 00:00:00' AND sip_timestamp < '2026-07-29 00:00:00'

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The same 22 years of US equities and 12 years of options data are queryable in SQL or plain English. A free account runs 100 queries a day and takes no card.

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