For each product type and month, the chart shows the percent of accidents involving that product that took place in that month. For example, in 2014, just over 70% of all ER visits related to Fireworks occured in July. The products are sorted from most to least seasonal, ending with "stair/steps" accidents which are essentially equally likely in any month.

The dashed line at 8.3% shows an "average" month. The y-scale emphasizes values between 0 and 20%, to better reveal the differences in seasonality between 0 occurances and 2x an average month.