Glossary

Definitions of key terms.

A

as_of - Query parameter that returns the version of each row Snowtrail held and the market could have seen on a given date, under the current model, back to the product's effective start.

B

Bcf - Billion cubic feet, a unit of natural gas volume.

C

CDD - Cooling Degree Days, a measure of cooling demand.

Coincident - A relationship measured in the same period (for example GLMI against the same-month JKM-TTF spread). A coincident result is not a lead and not a forecast.

H

HDD - Heating Degree Days, a measure of heating demand.

Henry Hub - The primary US natural gas pricing point.

L

LNG - Liquefied Natural Gas.

M

mcm - Million cubic meters.

model_version - MAJOR.MINOR version of the model that produced a row. A MAJOR increment restates history.

N

NBP - National Balancing Point, UK gas trading hub.

P

Point-in-Time (PIT) - Data as known at a specific historical moment.

S

Signal - A quantitative indicator derived from fundamental data.

Structure-preserving null - A second significance test (for example a circular shift) that keeps the signal's own persistence. Since 2026-09-29 a headline is significant only if this p-value and the block-permutation p-value are both below 0.05.

SUPERSEDED - event_status of an event that a later data revision no longer supports. It is kept, not deleted.

T

TTF - Title Transfer Facility, main European gas trading hub.

V

Vintage floor - The date raw object versioning began; nothing earlier can be reconstructed. The effective as_of start, set by when each row's inputs arrived, is later for every product (2026-02-23 to 2026-09-24). An earlier as_of is not rejected; it returns only rows stamped by then. See Point-in-Time Integrity.

W

Working Gas - Natural gas in storage available for withdrawal.