United States firms in the early 20th century were subject to public and private regulation. Forms of regulation included rate regulation and stock exchange listing requirements. These regulations created incentives to report income statement information. This study utilizes the 1915 Moody’s Analyses of Investments to test whether regulated firms in the United States reported more income statement information than unregulated firms. Rate regulation influenced utilities to report income statements more frequently than industrial companies.

Stock market listing requirements also influenced the reporting of income statements. Therefore, the results indicate that both public and private regulations influenced financial reporting in the early 20th century. Another finding of the study is that income statements were more frequently reported than balance sheets for both railroads and utilities.