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.)
Either way, the strip steak comes from the beef short loin subprimal, and it starts off with a short loin that has had the tenderloin removed, to produce a bone-in strip loin. (Leave the tenderloin in and you'd get T-bone and porterhouse steaks, rather than strip steaks.)