Americans' confidence in the economy rose in May for the third straight month in a row, fueled by growing optimism about future job prospects.

Still, the worry is that such improvements in shoppers' mood may be reversed amid huge falls on Wall Street fueled by fears that a debt crisis in Europe could hammer global growth.

The Conference Board, based in New York, yesterday said its Consumer Confidence Index rose to 63.3, up from a revised 57.7 reading in April. Economists surveyed by Thomson Reuters had expected 59.

The increase was boosted by consumers' outlook over the next six months, one component of the index, which soared to 85.3 from 77.4, the highest seen since it hit 89.2 in August 2007, before the economy entered into a recession.

The other component of the index, which measures how shoppers feel now about the economy, increased to 30.2 from 28.2.