___United Continental posts 4Q loss as traffic falls Travelers avoided United Airlines last year, leaving it with a fourth-quarter loss as it continues to pay for its stumbles in absorbing Continental. United Continental Holdings Inc. on Thursday reported a $620 million loss for the quarter as passenger traffic dropped 3.2 percent. The loss was driven by $408 million in spending on the integration for things such as training and repainting airplanes. Superstorm Sandy hurt profits by $85 million, too. ___ Southwest's 4Q profit slips on higher costs DALLAS (AP) â¿¿ Southwest Airlines Co. said Thursday that fourth-quarter earnings fell by nearly half as costs rose for fuel, labor and maintenance. The airline's revenue climbed slightly, however, as the average fare increased by almost $8 from a year ago. Southwest said that bookings for the first three months of 2013 look strong. It said that based on bookings and ticket prices so far, a key revenue measure should rise by between 2 and 3 percent in January compared with the same month last year. Although the rate of airfare increases has slowed since 2011, fares are still going up partly because airlines are limiting the number of flights, making seats scarcer. Southwest expects the industry as a whole to run about 1 to 2 percent fewer flights in early 2013 than in the same period last year. ___ 3M says 4Q profit rose 3.9 percent MINNEAPOLIS (AP) â¿¿ Post-it notes and other office products helped lift 3M's fourth-quarter profit, despite a slowdown in other parts of its business. The Maplewood, Minn.-based company earned $991 million, or $1.41 per share, up 3.9 percent from a year earlier. The results matched expectations of analysts surveyed by FactSet. 3M said profits grew in its consumer and office business, which makes Scotch tape and Post-it notes, as well as in its health care unit. Profits fell in all four of its other divisions, which make things like industrial products and construction materials.