S.C. Code Regs. § § 103-18
Each railroad company shall file in the office of the Commission quarterly reports, on or before the last day of the month following the quarter for which the report is made, showing fully and in detail the revenues and expenses of such company during the reporting quarter and cumulatively for the year.
Each railroad company, railroad terminal company, or express agency employing rail services and facilities, shall, on or before the thirty-first day of March of each year file in the office of the Commission an annual report, duly sworn to, showing fully and in detail the operations of such company or agency during the preceding fiscal year, to-wit: From January the first to December the thirty-first, both inclusive.
All of said reports shall be rendered on, and in accordance with, the printed forms that the Commission will prescribe and furnish for that purpose.
In addition to the foregoing, each of said companies or agencies shall furnish such other reports and information as the Commission may require from time to time.
Furthermore, it shall be the duty of each of said companies or agencies to produce, for the inspection of the Commission, any and all books, papers, contracts, agreements and other original records, of any character whatsoever, that may be in possession of said company or agency, or within its power, custody or control, or copies, thereof, as may be demanded and designated by the Commission.
S.C. Code Regs. § 103-18