Should I include foundation depth in story height?

[Tstruct]

My current practice is I don't include foundation depth in story height which means:
Story height = foundation's top to next slab's top.
Similar approach is used in retaining walls. But recently I got into a discussion where other person's opinion was to include foundation depth in story height which means:
Story height = foundation bottom to next slab's top.
What is your opinion?

 

[KootK]

The answer will depend on what you are designing when using "story height" as a parameter. If you're using it for earthquake design then you'll want to consider the nuances associated with determining the appropriate seismic base level. If it's basement wall soil retention then it is pretty common to consider the basement slab on grade as laterally supporting the base of the wall.