The data is based on the movement of commercial crude oil inventories of U.S. companies. When crude oil inventories increase, the market is oversupplied with crude oil, while a decrease in crude oil inventories indicates a strong demand for crude oil. When the published value is higher than expected, it is negative for crude oil and positive for the U.S. dollar; when the published value is lower than expected, it is positive for crude oil and negative for the U.S. dollar. Since crude oil exports make up a large part of the Canadian economy and are mainly exported to the U.S., the increase or decrease in EIA crude oil inventories will also have an indirect effect on the Canadian dollar.