The rally in the oil market came to a halt Friday after new data showed U.S. oil producers increased the number of rigs drilling for oil–by one–raising worries that the hoped-for decline in output may not come to pass. Oil-field services company Baker Hughes Inc. said Friday that the count of drilling rigs in the U.S. rose by 1, ending three straight months of weekly declines. Since their depths last month, oil prices have rallied more than 50% in the expectation that the lower prices would curtail production, even as supply-and-demand fundamentals remained weak. The number of oil rigs actively drilling in the U.S. has fallen more than 50% from year-ago levels, but production has declined by less than 7% and still remains more than 9 million barrels a day. But the rally to the $40-a-barrel level–and the increase in the rig count, however marginal–raises the possibility that the […]