Half of the nation’s 40 biggest publicly traded corporate spenders have announced plans to curtail capital expenditures this year or next, according to a review by The Wall Street Journal of securities filings and conference calls.

Nationwide, business investment in equipment and software—a measure of economic vitality in the corporate sector—stalled in the third quarter for the first time since early 2009. Corporate investment in new buildings has declined.

At the same time, exports are slowing or falling to such critical markets as China and the euro zone as the global economy downshifts, creating another drag on firms’ expansion plans…

“The whole world is looking for stability and clarity from the United States,” said David Seaton, chief executive of Fluor Corp., FLR +0.73% a large engineering and construction firm. If uncertainty isn’t removed, he said, “people will sit on their war chests of cash and return it to shareholders. You’ll have a retarded growth trajectory.”