Paper Trading Before Real Money
One session shape: median quoted spread by half-hour bucket, Ford (F), recent completed sessionsseries ·
2026-08-22 · 13×3
Five years of sessions: share closing above the open, typical move, and the extremes (SPY, 2021-2025)table ·
2026-08-22 · 5×6
What a real fill costs: median quoted spread in bps of the midpoint, regular hours, recent completed sessionsranking ·
2026-08-22 · 6×4
One session shape: median quoted spread by half-hour bucket, Ford (F), recent completed sessions
One session shape: median quoted spread by half-hour bucket, Ford (F), recent completed sessions
| et_time | spread_bps | quote_updates_m |
|---|---|---|
| 09:30 | 7.16 | 0.06 |
| 10:00 | 7.15 | 0.07 |
| 10:30 | 7.16 | 0.04 |
| 11:00 | 7.19 | 0.04 |
| 11:30 | 7.19 | 0.03 |
| 12:00 | 7.08 | 0.02 |
| 12:30 | 7.06 | 0.02 |
| 13:00 | 7.18 | 0.02 |
| 13:30 | 7.19 | 0.02 |
| 14:00 | 7.08 | 0.03 |
| 14:30 | 7.1 | 0.02 |
| 15:00 | 7.14 | 0.03 |
| 15:30 | 7.16 | 0.05 |
the exact SQL behind every number
SELECT formatDateTime(toStartOfInterval(toTimeZone(sip_timestamp, 'America/New_York'), INTERVAL 30 MINUTE), '%H:%i') AS et_time,
round(quantileExactIf(0.5)(toFloat64(ask_price - bid_price) / (toFloat64(ask_price + bid_price) / 2), bid_price > 0 AND ask_price > bid_price) * 10000, 2) AS spread_bps,
round(count() / 1e6, 2) AS quote_updates_m
FROM global_markets.cache_stocks_quotes
WHERE ticker = 'F'
AND sip_timestamp >= toDateTime(today() - 10)
AND sip_timestamp < toDateTime(today() - 3)
AND (toHour(sip_timestamp) * 60 + toMinute(sip_timestamp)) BETWEEN 810 AND 1199
GROUP BY et_time
ORDER BY et_time
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