Online retail spending reached $39 billion in the fourth quarter 2009, up 3 percent versus 2008, comScore announced Tuesday. The fourth quarter increase marks a return to positive growth after four consecutive quarters of year-over-year declines.

comScore stated that the growth in spending was driven by an increase in online buyers, while average spending per buyer saw modest declines. Online retail spending for 2009’s third quarter totaled $29.5 billion, reflecting a 2 percent decrease from the same quarter in 2008.

For the full year 2009, total retail e-commerce spending reached $129.8 billion, marginally below the previous year's total of $130.1 billion. comScore noted that throughout the year Amazon and Wal-Mart, the largest online retailers, gained market share of e-commerce sales at the expense of small and medium-sized retailers.

"The fourth quarter, with 3 percent year-over-year growth, helped end what has been a disappointing year for online consumer spending on a more positive note," said comScore Chairman Gian Fulgoni.

"As we head into 2010, there is reason for guarded optimism for online retail spending to continue to gain share of consumers' wallets. At the same time, I expect absolute growth to be stymied by continued high unemployment and the deleveraging that is occurring in the economy as consumers exercise their new-found propensity to save."