I'm not sure if this will work for your true setup,
but maybe you can try unioning the table to itself.
Then you can use formulae such as:
IF [Table Name]="Sheet1" THEN [Sampling Planned] ELSE [Samp Finished] END
Similarly for [EndTime]:
IF [Table Name]="Sheet1" THEN [Eval Planned] ELSE [Eval Finished] END
Then duration is:
Please see workbook v10.3 attached in the Forum Thread.
282901dual2.twbx 15.5 KB