Day-of-month and the gap between consecutive settlement dates: the twice-monthly cadence

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 When Is Short Interest Released?.

Rows × columns

16 × 3

Period covered

2025-12-15 to 2026-07-31

Computed

2026-08-22

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

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 2026-08-22, and the query below is what returned them.

SELECT settlement_date,
       toDayOfMonth(settlement_date) AS day_of_month,
       dateDiff('day', prior, settlement_date) AS days_since_prior
FROM (
    SELECT settlement_date,
           lagInFrame(settlement_date) OVER (ORDER BY settlement_date) AS prior
    FROM (
        SELECT DISTINCT settlement_date
        FROM global_markets.stocks_short_interest
        ORDER BY settlement_date DESC
        LIMIT 17
    )
    ORDER BY settlement_date
)
WHERE prior > toDate('2000-01-01')
ORDER BY settlement_date