The default STDEV_TIME setting for DeltaV modules is 0. STDEV_TIME is the standard deviation time basis for the standard deviation calculations. I have never seen a site that correctly configured their STDEV_TIME parameters. Does this mean the Large Variability metric is not fully utilized? My current understanding is that if you do not have an accurate STDEV_TIME setting then you will not have accurate standard deviation calculations. For fast loops, such as flow controllers, the STDEV_TIME default of 0 is acceptable. But for slower controllers such as level controllers, the default value will result in significantly incorrect variability calculations and therefore metrics. Is this correct? Does anyone have a suggested methodology for efficiently assigning STDEV_TIME to all modules as necessary? How do determine STDEV_TIME for all modules quickly? I have considered Entech or bulk assumptions that I wont get into here. Any recommendations/thoughts would be greatly appreciated