You will note I employ use of the terms ‘claimed’ and ‘unclaimed’ as opposed to the terms ‘allowable’ and ‘unallowable’. Several years ago I began pushing for this characterization due to the negativity of the term ‘unallowable’. Congress and regulators, in their infinite wisdom, may decide not to support a normal business cost such as interest but auditors, as normal human beings, tend to begin to think of unallowable costs as bordering on evil.
Further, by moving to the term ‘claimed’ as opposed to ‘allowed’, the ownership of the decision of how to identify the costs is associated properly with the contractor. The tone changes to the contractor ‘claiming’ the costs as opposed to the government ‘allowing’ the costs.