Expected Move vs. Realized Move: The Crush Edge

Every earnings print comes with a price tag on uncertainty. That price tag is the expected move: what the options market is charging, right now, for the weekend of drama ahead of the report. The realized move is what actually happens afterward. Premium sellers live in the gap between those two numbers.

What the expected move actually is

Take the at-the-money call and put with the expiry that covers the report. Add their mid prices. Divide by the stock price. That fraction is the market’s one-standard-deviation-ish bet on how far the name can travel through the print. It is not a forecast from a sell-side desk. It is a clearing price for insurance.

IV crush is the reason that number matters. When the report hits, a large slice of event uncertainty disappears. Implied vol falls. Option premium that was priced for a wide range suddenly looks expensive relative to the smaller range left behind — unless the stock actually travels that far.

Build a realized-move history

Pull the last six to eight earnings dates for the ticker. For each, measure the absolute percentage move from the prior close into the first full session after the print (or into the open if you trade the gap). Write down the median and the 75th percentile. Those two numbers are your baseline for “normal” and “hot.”

Now compare:

• If expected >> median realized, sellers have cushion. The market is charging for a bigger move than history usually delivers.
• If expected ≈ median realized, the crush edge is thin. You are mostly collecting fair premium for fair risk.
• If expected << recent realized, buyers have the narrative — or the name has changed character (new product cycle, new float, new macro beta).

Do not treat a single outlier print as the new normal. One 12% gap does not rewrite a median of 4%. It does remind you that defined risk exists for a reason.

Where scanners help — and where they don’t

An IV-crush scanner that tags hazard or toxic is usually combining elevated IV rank, a rich expected move versus history, and a short countdown. That is a research filter, not a sell ticket. Two names with the same expected-vs-realized spread can have wildly different liquidity, borrow, and gap behavior.

Always check:

1. Bid-ask width on the strikes you would actually sell
2. Open interest and volume on those strikes
3. Whether the expected move is measured on a weekly or a monthly that still has days of non-event theta
4. Whether the stock has a habit of multi-day post-print drift (crush on day one, trend on day two)

Structures that respect the gap

If the expected move looks rich, the classic defined-risk answers are iron condors and credit spreads with short strikes outside the expected move. You are not trying to predict direction. You are trying to sell a range the market overpriced.

Calendar spreads are the cousin trade: short the front expiry that holds the event, long a further expiry at the same strike. Front IV collapses harder than back IV. The differential is the thesis. Calendars hate a violent directional gap, so size them like spreads — not like lottery tickets.

Naked short straddles maximize premium and maximize left-tail pain. Most retail accounts that blow up around earnings were not wrong about the crush; they were wrong about sizing when the realized move finally printed larger than expected.

A rehearsal loop worth keeping

Before the next earnings week, pick three names the scanner flags. For each, write the expected move, the median realized, and the structure you would sell — strikes, max loss, and exit rule. Then run the whole sequence on Stock Picks with paper size. Log whether you would have held through the first thirty minutes after the open or scratched into the crush.

The edge is not a slogan. It is a spreadsheet habit: expected versus realized, over and over, until you can feel when premium is stretched and when it is merely noisy. Nothing here is financial advice. Live markets punish improvisation; paper markets forgive it long enough to teach you the difference.