Variance analysis is a method used to compare planned project performance against actual performance.
Since the project sponsor has requested a performance report for the entire 10-year initiative, variance analysis would allow the risk manager to identify discrepancies between what was planned and what has been achieved over the course of the project. This analysis is crucial for understanding performance trends, cost deviations, schedule variations, and overall project health.
PMI's guidelines support the use of variance analysis in performance reporting as it provides insights into how well the project is adhering to its planned budget, schedule, and scope.