Answer :
Answer: The Business Cycle Dating Committee of the National Bureau of Economic Research.
Explanation:
The Business Cycle Dating Committee under the National Bureau of Economic Research are tasked with declaring the beginnings and the endings of the Business cycle. They do this by reviewing Economic wide measures especially GDP to see if prevailing conditions are still ongoing.
To declare a Recession, the Economy would have to be experiencing a significant downward trend in widespread economic activity reduction over more than a couple of months but for a Recession to be declared as over and back to a Peak, it might take longer than that.