The International Labor Organization reports that productivity in the United States accelerated in 2002, surpassing Europe and Japan in terms of annual output per worker for the first substantial period since World War II.

Globally, the ILO study finds growth in productivity per person increased from 1.5 percent during the first half of the 1990s, to nearly two percent in the second half.

The report notes most of this growth was concentrated in industrialized economies as well as in some Asian nations, notably China, India, Pakistan and Thailand. But data shows a decline in total productivity growth in African and Latin American economies.

The study says the United States is about twice as productive as the European Union and Japan. But it attributes part of the difference in per worker output to the fact that Americans work longer hours than their European counterparts. When measured on an hourly basis, the ILO finds European workers to be more productive.

ILO economist Dorothea Schmidt notes that the work week in many European countries is shorter than that in the United States. Yet, figures for Norway, France and Belgium show people produce more for every hour they work than do those in the United States.

"And the why? I think there are many, many reasons," explained Ms. Schmidt. "One might be that during the time that these people work, they work more efficiently. It might be that the technology they use enables them to be more efficient in this one hour. I think if you work 15 hours a day, of course there are hours that are not as productive as if you work six hours a day."

For the first time, the ILO examines agricultural productivity. It notes that this sector remains the primary employer in many developing economies. Yet, productivity levels in agriculture remain higher in richer countries than in poorer ones.

For example, the study finds that an agricultural worker in the United States produces more than 650 times more than an agricultural worker in Vietnam.

Ms. Schmidt says a lot of the difference can be attributed to the modern technologies and the large subsidies received by farmers in the United States and in the European Union.

"If you talk about developing countries, it is not really fair to say these people are not efficient," she added. "They are working hard. They are probably working harder than other people. But it is just that they do not have the technology that they cannot perform that well. But, having said that, I think the fact these modern technologies are used are also the outcome of subsidies. So this is actually just going hand in hand."

The ILO says agrarian economies eventually will have to shift to more modern ones. But for the time being, they say, measures must be taken to improve their productivity, to help reduce poverty.