N.Y. Comp. Codes R. & Regs. tit. 9 § 1645-2.1
Every transaction involving investments can be broken down into component elements, such as purchase or sales price, accrued interest purchased or sold, expense of acquisition or disposition, etc. Some or all of these elements will be present in every investment transaction. For example, some securities are bought and sold on the open market. Some may be bought through brokers who charge a commission, others may be bought through banks which may not charge a commission. Others, like certain U.S. bonds, are not traded on the open market, but may only be bought from, or redeemed by, the issuer or its agents. The agents, in the latter case, may or may not be entitled to compensation. Some securities may be bought and sold, or redeemed, at face value, with or without accrued interest; other transactions may involve discounts from face value, or premiums; interest may be receivable periodically on some securities, on others the interest may merely accrue and be reflected in increased redemption values, etc. The elements to be accounted for, some or all of which will occur in every investment transaction, are summarized as follows:
N.Y. Comp. Codes R. & Regs. Tit. 9 § 1645-2.1