Featured analysis
Who Sets the Ex-Dividend Date? Not the Board
Who sets the ex-dividend date? The listing exchange does, under FINRA uniform practice rules, working from the record date and the T+1 settlement cycle.
Market-data research
Strasmore Research
Educational explainers, recurring market-structure breakdowns, and historical deep-dives. Every number is sourced from a stored query against real market data.
Every figure is computed from real US stocks and options market data and stored with the post, so the prose cannot drift from the data.
426 data-backed analyses · 204 evergreen explainers · Updated
- Held vs Not-Held Orders: Broker Discretion Held vs not-held orders: one obliges your broker to fill right now, the other hands them time and price discretion. See what changes, and what to ask.
- What Time Do Mutual Fund Prices Update? Mutual fund prices update once a day: NAV is struck at the 4:00 p.m. ET close and published that evening. See the timeline and why your order fills blind.
- Hard-to-Borrow Lists and Borrow Fees Why a hard-to-borrow stock costs a fee to short: how the locate works, who lends the shares, what the short owes on dividends, and how recalls force buy-ins.
- Warrants vs Call Options: Key Differences Warrants vs call options: a warrant is issued by the company and prints new shares on exercise, a listed call does not. See the dilution in real data.
Learn / market data & trading concepts
All 204Evergreen explainers of how US markets actually work, each concept taught with real, queryable market data.
- What Is an Ex-Dividend Date? How It Works The ex-dividend date decides who gets paid: buy before it and the dividend is yours, buy on it and it isn't. See the four key dates on real US timelines.
- The Option Greeks Explained: Delta to Rho Delta, gamma, theta, vega and rho, the five option greeks, demonstrated by tracing one real SPY call through its whole life against the stock.
- What Is VWAP? Volume-Weighted Average Price VWAP stands for volume-weighted average price. Definition: price times volume divided by total volume, reset daily. What it means on a real trading day.
- What Is a Bid-Ask Spread? Real Costs Learn what a bid-ask spread is, how to calculate it, and what it costs per trade, with real spreads measured from tick-level quote data on US stocks.
- What Is RVOL (Relative Volume)? How to Read It RVOL (relative volume) is a stock's volume ÷ its 20-day average: above 1 is busier-than-usual trading. Plus intraday time-of-day RVOL and what counts as high.
- What Is the Closing Auction? (Closing Cross) What the closing auction is, why one 4 p.m. print sets the official close, and how market-on-close orders feed the day's biggest trade, on real tape data.
- How Do Market Makers Make Money? The Spread What market makers do and how they earn the bid-ask spread, with real tick data: measured spreads, quote updates per second, and the SQL behind every number.
- Short Interest vs Short Volume: The Difference Short interest and daily short volume measure different things. See real per-ticker numbers, days-to-cover math, and the exact query behind every figure.
- What Is the 2s10s Spread? Yield Curve Data What the 2s10s spread is, how the Treasury yield curve works, and what past inversions looked like, with every chart built from auditable market data.
- Stock Market Holidays 2026–2027: NYSE & Nasdaq When is the stock market closed? Every upcoming NYSE & Nasdaq holiday and 1:00 p.m. early close for 2026–2027, from the live exchange calendar.
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