The Generally Accepted Accounting Principles exist to ensure that American accountants are using the same or almost the same standards so that comparison of financial statements between or within a company is easy and accurate. They also promote transparency in accounting. The GAAP are set by the FASB.
According to the FoodTV Encyclopedia for Delmonico Steak, the Delmonico steak is a boneless top loin steak, which is also called a New York strip steak and a Kansas City strip steak. (With the bone in, it is usually called a club steak.)
The Delmonico Steak served by the current iteration of Delmonico's in New York is a boneless ribeye. Bone-in top loin steak: (a triangular-shaped, short loin cut, some suggesting the first cut of the top loin next to the rib end) also known as a club steak, country club steak, shell steak, and strip loin steak).