UCLA Department of Statistics

2008 Archives

Statistical Analysis of Gasoline and Diesel Loss Rates at Retailers

Xiaofei Yan

It has been known in petroleum industry that fuel expands when the temperature increases and contracts when the temperature decreases. Gasoline has 1% volumetric change for every 15 degree F change, and diesel has 0:6% volumetric change for every 15 degree F change. There have been a 60 degree Fahrenheit standard for temperature correction of bulk deliveries of petroleum products. However, as the temperatures the fuel was sold at were above 60 degree F at many states, it is said every year overall 670 million additional gallons of gasoline and 90 million additional gallons of diesel were consumed in U.S. because of the fuel expansion. Laws and rules about installation temperature-corrected kits at dispensers are already on the way in many U.S. states. However, besides the interests of the individual consumers, the retailers who purchase bulks of fuel from wholesaler are also experiencing the loss caused by fuel expansion. For the sake of fairness, it is necessary to find evidence of fuel loss for the retailers if there are litigations in the future. The purpose of this project is to determine whether retailers were experiencing constant fuel loss, and what environmental elements might influence on such fuel loss. It is also interesting to see whether the pattern of the fuel loss can be fitted by any models.