IFC exporting volume as cubic feet.

New Revit user here, so this may very well be operator error, but here is my issue: 

Im a surveyor in industrial construction, and when I export an IFC, I need volume (concrete, for my purposes) to be represented as cubic yards, not cubic feet. My project units in Revit are set to cubic yards, and I can’t figure out how to get the IFC file to keep it as cubic yards. Can someone please help? Thank you.