EIA weekly inventory report
The US Energy Information Administration's weekly data on crude, gasoline and distillate stocks, normally released Wednesdays at 10:30 a.m. Eastern.
The EIA Weekly Petroleum Status Report gives US commercial crude, gasoline and distillate stocks, refinery utilization and exports for the prior week. Crude stocks are reported nationally and for Cushing, Oklahoma and the Gulf Coast. The EIA publishes a separate weekly natural gas storage report, normally on Thursdays.
Traders care because the report is a regular, high-impact data point. A crude draw larger than expected often supports prices, and a larger build tends to weigh on them. Compare the actual change with the consensus estimate, not with zero, because the market prices surprises.
Worked example (illustrative numbers, not real data): consensus expects a crude build of 2 million barrels, and the report shows a build of 4 million barrels. The 2 million barrel surprise is the figure traders react to.