MnROAD underwent a large-scale reconstruction project during the summer of 2008, and several of its test sections were surfaced with hot mix asphalt. It is important that researchers obtain all material properties from all pavement materials used, but one of the most vital metrics is the amount, or percent, of air voids in the mixtures. The goal of this project was to gather this information. Researchers collected data from 145 cores from various MnROAD cells and tracked the change in air voids over time. Analysis of the data was not part of this study.