(2) No public utility shall keep any other accounts or records of its public utility business transacted than those prescribed or approved by the commission except such as may be required by the laws of the United States.
(3) The commission shall cause to be prepared suitable blanks for reports for carrying out the purposes of this chapter, and shall, when necessary, furnish such blanks for reports to each public utility. [Amended by 1971 c.655 §86]