Creating Calculations Based on Process Data

Browse into the Plant Model.
Right-click on a Group and select "New Variable"
Type in the name of the new Variable. Variable names must be unique within a given Production Unit.
Select the new variable; right-click and select "Variable Sheet"
Make sure the "Data Source," "Event Type," "Sampling Interval," "Sampling Offset," "Sampling Type," and "Input Tag" are visible. Select the "Column/Row Visibility" icon in the Variable Sheet window toolbar to change column visibility.
Select the appropriate columns in the "Hidden" list and move them into the "Visible" list by selecting the ">" button.
Close the "Column/Row Visibility" Dialog To Return To the Variable Sheet window.
Select a Data Source of "PI," an Event Type of "Delay," and a Sampling Type of "Average."
If the Input Tag that will drive the calculation is known, then type it into the Input Tag column. To search for a Tag, select the Input Tag column, right-click, and select "Tag Search."
Search for an appropriate Tag, select a Tag from the search results, and select "OK."
The selected tag will appear in the Input Tag column.
To save the variable, select the "Save" icon in the Variable Sheet window toolbar.