Plots six key statistics of secondary eyewall replacements (SERs). The first plot just shows the probability of storms with the number of SERs given on the x axis. The second plot shows the mean and standard deviation of lifetime maximum wind speed among the events with the number of SERs given on the x axis. The third plot shows the mean and standard deviation of wind speed integrated over the life of each event, among the events with the number of SERs given on the x axis. The final three plots are identical to the first three except that they show statistics of “primary eyewall replacements” (PERs), which occur when a new eyewall forms inside an existing eyewall and eventually replaces it. This phenomenon happens during the decay phase of some simulated tropical cyclones.