Model data is generated from performance information sorted by day of the week, time period, and process status by a performance information analysis section and a process status analysis section. An abnormality determination section detects abnormality using appropriate model data. What the graph of an expected status is like, how much the graph of the current status that has been determined abnormal differs from the graph of the expected status, and how much the current status is like the expected status are displayed allowing a system manager to observe detailed information about abnormality determination.