Now Playing: 2-20-13 Marketplace

Sen. Mark Warner (D-Va.) discusses the sequester and the impact it could have on his region. Walmart is expected to deliver bad news to investors tomorrow, blaming the payroll tax increase for slow sales. A new survey from Pew offers details about why people take out payday loans even though they know they are getting a raw deal. Dartmouth University recently stopped offering credit for Advanced Placement courses. A New Hampshire city is trying out a new device designed to ease parking headaches. And in the latest installment of Freakonomics Radio, Stephen Dubner talks about why the government is making less money from gas taxes, despite the rising prices at the pump.