AnimationBehavior.Accumulate (PowerPoint)
Determines whether animation behaviors accumulate. Possible return values are msoAnimAccumulateAlways - Accumulates with other animation behaviors, msoAnimAccumulateNone - Does not accumulate.
Use this property in conjunction with the Additive property to combine animation effects. The value of the Accumulate property can be one of these MsoAnimAccumulate constants.
ActiveWindow.Selection.SlideRange(1).TimeLine.MainSequence(1).Behaviors(1).Accumulate = msoAnimAccumulateAlways