This is a calendar heatmap of mass shootings in the United States in 2015. Calendar heatmaps are useful for visualizing time-series data, but can also be impactful for the underlying patterns they reveal. The color shading above do not indicate the number injured or killed. They only indicate how many mass shootings happened on a particular day. Each vertical line of boxes represents the seven days of the week. Mouse over the squares to see more information.
NB: The chart does not include days where no mass shootings occurred.
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