What is the meaning of the values for NET_ZERO_ADJUSTMENT_ FLAG?

I found this description of the field NET_ZERO_ADJUSTMENT_FLAG on table pa_expenditure_items_all in eTRM:

Flag that indicates whether the item is fully reversed or the item is one of the adjusting items that fully reverse another item. Generate Draft Invoice uses the flag to exclude fully reversed, uninvoiced items from a customer invoice.

So, if it is Y it is fully reversed and N it is an adjusting item that fully reverses another item?    Not sure which value belongs with which description.

Also, can burden be recalculated on a fully reversed expenditure?