The economy has bounced back quickly enough that the computer business will have seen a slight boost this year, Gartner said in a study published on Monday. The analyst group estimates that shipments will have overall climbed 2.8 percent in 2009 to about 298.9 million computers. It marks a sharp reversal from a forecast as late as September that had computers sinking 2 percent. A recovery of the sort is credited mostly to strong sales in the summer and "modest" anticipated growth in the summer.