The purpose of this project was to compare fine particulate matter 2.5 (PM_2.5) across U.S. Census tracts, specifically focusing on rural vs. urban differences between 2010 and 2019. Generally, rural areas had lower PM_2.5 levels than urban areas, pollution decreased faster in rural areas than in urban areas, and rural and urban areas with higher proportions of Black, Hispanic, and residents in poverty had higher PM_2.5 levels.