When a consideration is executory, it is not indispensable that the contract should specify its amount or the means of ascertaining it. It may be left to the decision of a third person or regulated by any specified standard.
N.D. Cent. Code § 9-05-06
Executory consideration - Method of ascertaining
Official source: North Dakota Legislative Branch. Reproduced from public-domain North Dakota statutes; confirm against the official source for the current text. Not legal advice.