A & A Enterprises ships integrated circuits to companies that assemble computers. Because computer manufacturing operations run on little inventory, parts must be available when promised. Thus, a critical element of A & A’s customer satisfaction is on-time delivery performance. To ensure that the delivery process is performing as intended, a quality improvement team decided to monitor the firm’s distribution and delivery process. From the A & A corporate database, 100 monthly shipping records were randomly selected for the previous 21 months, and the number of on-time shipments was counted. This information is contained in the file A & A On Time Shipments. Develop the appropriate 3-sigma control chart(s) for monitoring this process. Does it appear that the delivery process is in control? If not, can you suggest some possible assignable causes?