8. The head of the surgery department is concerned about the incidence of patient readmissions after being discharged from the hospital. In several cases, a patient had to be readmitted multiple times. The following data are available for the past 11 months. Develop the appropriate control chart and help the head of surgery determine whether the process involving readmissions per 500 discharges is stable.

Based on your findings, does he have a reason to be concerned?