Time series examples for the full record of 1-hour ozone at the rural background site Mesa Verde National Park (top), the urban Golden NREL (middle), and Welby (bottom). Statistical analyses of these data with box-whisker plots (see data processing section for box-whisker format explanation), representing each year of data, are shown to the right. DOI: https://doi.org/10.1525/elementa.300.f5