When we last checked in with government statisticians, they though the economy grew at an annual rate of 1.7 percent. Today, a surprisingly strong revision upward. Now, gross domestic product grew 2.5 percent from April to June, which helps build the argument that the Federal Reserve will ratchet back on its stimulus program. Diane Swonk, chief economist at Mesirow Financial in Chicago, tells Marketplace what this means for the economy.