Get Expiry Rolloff

Dealer gamma grouped by expiration — what leaves, and when.

The nearest tranche is the single largest scheduled change to the surface and the one thing a same-day snapshot cannot show: at its close that gamma stops existing whether or not anybody trades. A trader who knows 38% of the book expires tonight reads tomorrow's map differently.

share is computed on ABSOLUTE gamma so an internally offsetting tranche (a big call wall against a big put wall) still reads as large — all of it is leaving, and the offset does not survive the expiry.

"Is that a lot?" is answered by context: the percentile of today's share against this symbol's stored sessions, plus the plain word for it. Until enough sessions are stored, percentile is null and the raw share stands on its own — which is still interpretable, just not ranked.