In 2013 the Government Accountability Office published a report which concluded that "repealing or amending the Jones Act cabotage law might cut Puerto Rico shipping costs" and that "shippers believed that opening the trade to non-U.S.-flag competition could lower costs". The same GAO report also found that "doing business in Puerto Rico that GAO contacted reported that the freight rates are often—although not always—lower for foreign carriers going to and from Puerto Rico and foreign locations than the rates shippers pay to ship similar cargo to and from the United States, despite longer distances. Data were not available to allow us to validate the examples given or verify the extent to which this difference occurred." Ultimately, the report concluded that "[the effects of modifying the application of the Jones Act for Puerto Rico are highly uncertain" for both Puerto Rico and the United States, particularly for the U.S. shipping industry and the military preparedness of the United States.