Box and whisker plots for present-day (2010–2014) ozone metrics for non-urban and urban sites. Present day ozone distributions for a) 4MDA8 (ppb), b) NDGT70 (days), c) SOMO35 (ppb day), d) 3MMDA1 (ppb) and e) AVGMDA8 (ppb) metrics showing regional urban and non-urban distributions. The box indicates the range from the 25th to the 75th percentile of the data (or the interquartile range (IQR)). The whiskers extend to 1.5 × IQR. Data beyond the whiskers are plotted as points and are considered as outliers. The line and the point in the boxes indicate the median and mean. The number of stations (N) in each box plot are marked in red. DOI: https://doi.org/10.1525/elementa.273.f6