They usually get trade promotion authority periodically, and it lasts for a period of five years or so. They take a period of time and they negotiate the various agreements under the TPA. If you go back, I think to 2007, they had a bipartisan consensus on basic issues they wanted to see in every trade agreement. People in Congress think it's unusual to let it go this long.
On June 5th, 2013. See this statement in context.