WASHINGTON—Almost half of U.S. chief financial officers believe a recession will strike the U.S. economy by the end of 2019, with the tight labor market and growing trade tensions driving economic jitters among corporate America.

Additionally, more than 80% of U.S. CFOs think a recession will strike by the end of 2020, according to the Duke University/CFO Global Business Outlook survey released Wednesday.

“All of the ingredients are in place: a waning expansion that began in June 2009—almost a decade ago—heightened market volatility, the impact of growth-reducing protectionism, and the ominous flattening of the yield curve which has predicted recessions accurately over the past 50 years,” said Campbell Harvey, a director of the survey.

Trouble finding and keeping qualified employees was the executives’ most-cited concern. The U.S. unemployment rate and layoffs have hovered at historic lows this year, shrinking the number of skilled workers available to hire, leading many business owners to lift wages and go to extremes to put people on payrolls.

The CFOs also were concerned about recent international trade disputes. The Trump administration’s growing trade frictions with foreign countries, particularly China, have led many firms to put investments and other business moves on hold until tensions clear up.