Target shoppers Kelly Foley (from left), Debbie Winslow and Ann Rich use a smartphone to look at a competitor's prices while shopping shortly after midnight on Black Friday, in South Portland, Maine.
Robert F. Bukaty/AP
A New York Stock Exchange trader works on the floor on Dec. 17. Stocks rose nearly 300 points after the Federal Reserve announced it plans to begin raising interest rates next year.
Andrew Burton/Getty Images
Fuel prices have plummeted this year, but airfares have remained high. The International Air Transport Association estimates that the world's airlines will rake in nearly $20 billion in profits this year.