Reference
Glossary
The terms the brief uses, defined the way the propane trade says them.
- PADD (Petroleum Administration for Defense District)
- The five regions EIA reports petroleum data by. PADD 1 is the East Coast (split into 1A New England, 1B Central Atlantic, 1C Lower Atlantic), PADD 2 the Midwest, PADD 3 the Gulf Coast, PADD 4 the Rockies and PADD 5 the West Coast. Weekly propane stocks report PADD 4 and 5 combined.
- Mont Belvieu
- The storage and trading hub east of Houston where US propane is priced. Salt caverns there hold the country's largest concentration of NGL storage, and the daily spot price at the hub is the benchmark wholesale and retail prices key off. When someone in the trade says "the market moved", they usually mean Belvieu.
- Weekly Petroleum Status Report (WPSR)
- EIA's weekly report, out Wednesday mornings, covering the prior week. Source of the stocks, production, imports, exports and product supplied figures on this site.
- Residential price survey (SHOPP)
- EIA's State Heating Oil and Propane Program: a weekly survey of residential and wholesale propane prices by state, published Wednesday afternoons during heating season only, October through March. Off season those pages show last winter's readings and say so; the series are paused by design, not broken.
- Propane/propylene
- EIA's weekly inventory series counts propane and propylene together because they share storage and pipeline infrastructure. Propylene is mostly petrochemical feedstock, not heating fuel. We say "propane stocks" in running copy and never build an argument on the split.
- Primary storage
- The bulk storage layer the weekly stocks number covers: refineries, gas plants, pipelines and bulk terminals. It excludes secondary storage (dealer plants and bulk tanks) and tertiary storage (the tank behind the house). Retail supply can feel tighter than the primary number looks, because the last two layers are invisible to it.
- Days of supply
- Also called domestic product-supplied coverage: primary stocks divided by the trailing-four-week average of domestic product supplied (EIA's own convention). The trade's yardstick for how long inventories would last at current demand. It is a coverage ratio, not a depletion forecast: it does not net out exports or account for demand changes, so it never predicts a run-out date. A summer figure always looks fat because summer demand is small; the number that matters is how it compares to the same week in prior years.
- Product supplied
- EIA's proxy for demand: the volume that left primary storage for the domestic market. Not retail sales, but the closest weekly read on consumption the public data offers.
- Draw / build
- A weekly decrease or increase in stocks. Heating season draws inventories down; the build season, roughly April through September, restocks for the next winter. The summer build is the market's main event while the price survey is paused.
- Export pull
- US propane exports, mostly loaded on the Gulf Coast for Asian and Latin American buyers. Exports are the biggest structural claim on the domestic build: when the pull runs hot, less of the summer build stays home for winter.
- Pre-buy / fixed-price contract
- A customer or dealer locking winter gallons at a set price during the summer. The highest-stakes seasonal decision the audience makes. We describe the market conditions around it; we never tell anyone when, or whether, to sign.
- Winter fill
- Topping tanks ahead of heating season, usually late summer into fall. Dealers schedule it to smooth winter logistics; customers take it for price certainty and fewer cold-snap deliveries.
- Keep-full vs will-call
- Two delivery arrangements. Keep-full: the dealer monitors usage and schedules deliveries automatically. Will-call: the customer calls when the gauge runs low. Will-call customers are the ones a price spike or a delivery backlog catches.
- Crop-drying demand
- The Midwest's fall demand spike: propane fires grain dryers after harvest, and a wet corn crop can tighten PADD 2 weeks before home heating does. The reason October propane stories are often about agriculture, not weather.
- Heating degree day (HDD)
- A measure of heating demand: how far the day's average temperature fell below 65°F, summed over days. More HDD means more heating load. We cite NOAA's LP-gas-customer-weighted HDD, which weights the places propane customers actually are.
- Retail-wholesale spread
- The residential survey price minus the wholesale survey price for the same area, in dollars per gallon. A broad gross-spread indicator between the rack and the tank, not an estimate of dealer profit margin: it still contains delivery, tank service, seasonality risk and overhead. Wide and widening reads one way for a marketer and another for a buyer; we report the number and leave the reading to you.
- Versus the 5-year median (vs-5yr-median)
- A series compared against the median value for the same calendar week over the prior five years. Our standard "is this normal" yardstick. EIA's own convention is the 5-year average; ours is the median, which one freak year cannot drag. We label it honestly everywhere.