A group of economists at the University of Chicago and University of Oxford working with researchers at Uber found the company’s main service generated $6.8 billion in consumer surplus in the United States last year. Steve Levitt, in a September 16 UChicago news article, notes that "I think our findings should change the policy discussion. To date, the conversation has revolved around the idea that there are people who are hurt by the service, mainly taxicab medallion owners. There's [been] little discussion of the benefit to consumers.” The team, consisting of Steve Levitt, Robert Metcalfe, Robert Hahn, Peter Cohen, and Jonathan Hall, used data from almost 50 million customer sessions in the company’s four largest U.S. markets - Chicago, Los Angeles, New York and San Francisco - to calculate the consumer surplus generated by Uber. The findings were released as a National Bureau of Economic Research working paper this month.