US stocks flat as dollar, slow growth hit revenues

US stocks traded flat Thursday as key companies including General Motors, Caterpillar and Procter & Gamble said the strong dollar and slow world growth had hit quarterly revenues.

About 30 minutes into trade, the Dow Jones Industrial was down 9.38 points (0.05 percent) at 18,028.89.

The broad-based S&P added 0.90 (0.04 percent) at 2,108.86, while the tech-rich Nasdaq Composite rose 3.50 (0.07 percent) to 5,038.67.

The slower global economy, weak foreign currencies and intensified competition took a toll on a number of companies in the January-March quarter.

Household and personal care goods maker P&G fell 0.7 percent after reporting the strong dollar weighed on its earnings from abroad, exacerbating the fall in sales in all five business divisions.

GM (-3.6 percent) missed first-quarter profit forecasts -- 86 cents a share compared to 97 cents expected -- with net revenue of $35.7 billion down 4.5 percent from a year ago.

3M, the materials and chemicals giant, said revenues fell 3.6 percent, in part from a $90 million negative hit to earnings from currency impacts. Shares sank 3.4 percent.

Caterpillar sales fell 4.1 percent, also hit by weaker currencies abroad and the slowing Chinese economy. But it beat first-quarter earnings expectations and raised its full-year forecast, sending its shares up 1.3 percent.

Online market eBay, which reported after the close of trade Wednesday, added 4.0 percent after beating revenue and earnings predictions in the quarter, earning upgrades from several analysts.

Shares of Facebook, which reported a 20 percent drop in profit in the first quarter but growth in users and mobile ads, moved 0.7 percent higher.

Miner Freeport McMoRan sank 3.2 percent.

Bond prices were unchanged from Wednesday. The yield on the 10-year US Treasury held at 1.98 percent and the 30-year at 2.67 percent. Bond prices and yields move inversely.