The Cary Plant produces a part for agricultural equipment. The plant produces to demand rather than maintaining significant inventories, so there can be significant fluctuation in monthly output. One of the significant cost items is maintenance and repair (M&R) costs. M&R consists of both routine and unscheduled costs. The plant manager is trying to understand what effect production volume has on M&R costs and is getting conflicting information from the machine operators (who believe that higher output is related to higher M&R costs) and the financial staff (who say that their analyses do not show this). Data on monthly output (in machine hours) and monthly M&R costs for the most recent two fiscal years follow: