Maryland Code, Public Utilities § 4-101

(1) does not violate any provision of this article;

(2) fully considers and is consistent with the public good; and

(3) except for rates of a common carrier, will result in an operating income to the public service company that yields, after reasonable deduction for depreciation and other necessary and proper expenses and reserves, a reasonable return on the fair value of the public service company's property used and useful in providing service to the public.