<P> Congress passed a minor amendment to the Act in 1903, the Elkins Act . Major amendments were enacted in 1906 and 1910 . The Hepburn Act of 1906 authorized the ICC to set maximum railroad rates, and extended the agency's authority to cover bridges, terminals, ferries, sleeping cars, express companies and oil pipelines . The Mann - Elkins Act of 1910 strengthened ICC authority over railroad rates and expanded its jurisdiction to include regulation of telephone, telegraph, and cable companies . The Valuation Act of 1913 required the ICC to organize a Bureau of Valuation that would assess the value of railroad property . This information would be used to set freight shipping rates . </P> <P> In 1935, Congress passed the Motor Carrier Act, which amended the Interstate Commerce Act to regulate bus lines and trucking as common carriers . </P> <P> Congress enacted simplifying and reorganizing amendments in 1978, 1983 and 1994 . </P> <P> Congress passed various railroad deregulation measures in the 1970s and 1980s . The Railroad Revitalization and Regulatory Reform Act of 1976 (often called the "4R Act") gave railroads more flexibility in pricing and service arrangements . The 4R Act also transferred some powers from the ICC to the newly formed United States Railway Association, a government corporation, regarding the disposition of bankrupt railroads . The Staggers Rail Act of 1980 further reduced ICC authority by allowing railroads to set rates more freely and become more competitive with the trucking industry . </P>

Cause and effect of the interstate commerce act