174.The length of the “phase-in” period is not inconsequential for exporting countries desiring certification. That period relates directly to the onerousness of the burdens of complying with the requisites of certification and the practical feasibility of locating and developing alternative export markets for shrimp. The shorter that period, the heavier the burdens of compliance, particularly where an applicant has a large number of trawler vessels, and the greater the difficulties of re-orienting the harvesting country's shrimp exports. The shorter that period, in net effect, the heavier the influence of the import ban. The United States sought to explain the marked difference between “phase-in” periods granted to the fourteen wider Caribbean/western Atlantic countries and those allowed the rest of the shrimp exporting countries. The United States asserted that the longer time-period was justified by the then undeveloped character of TED technology, while the shorter period was later made possible by the improvements in that technology. This explanation is less than persuasive, for it does not address the administrative and financial costs and the difficulties of governments in putting together and enacting the necessary regulatory programs and “credible enforcement effort”, and in implementing the compulsory use of TEDs on hundreds, if not thousands, of shrimp trawl vessels.