The numbers: Job openings in the U.S. fell slightly in July to a five-month low in a sign of slackening demand for labor, but layoffs remained extremely low and the number of people quitting hit an all-time high, typically a mark of a strong jobs market.

The number of open jobs slipped to 7.22 million in July from 7.25 million in the prior month, the government said Tuesday.

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What happened: Job openings fell among wholesalers and government, offsetting an increase in media and energy-related work such as oil extraction. Lower oil prices have forced drillers to cut back on employment.

The share of people who left jobs on their own, known as the quits rate, rose to 2.6% among private-sector employees. That matched a post 2008 recession high.

The only time the quits rate has been higher was in 2001, shortly after the government first began tracking how many people left their jobs.

The quits rate for all employees also rose a notch — the first increase in more than a year — to set an 18-year peak of 2.4%. Some 3.6 million workers quit — a record high.

The rate at which people quit tends to rise when the economy is strong and workers are confident they can find another job, often one that pays better.

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Big picture: Job openings are still quite high and easily exceed the 6 million Americans officially classified as unemployed, but companies aren’t filling positions as rapidly. The U.S. has added an average of 150,000 new jobs a month in the past six months, down from 232,000 in January.

The outlook for the labor market could weaken even further.

President Trump announced stiffer tariffs on Chines imports at the beginning of August, causing a brief swoon in stock markets and dampening the confidence of business. The global economy has also weakened amid the intensifying trade dispute with China, delivering a blow to farmers, manufacturers and other big exporters.

The U.S. economy can keep growing even if hiring slows, but only so long as companies shun layoffs. So far there’s no hard evidence that layoffs are on the rise.

What they are saying? “Weaker job openings are usually a sign of slower payroll growth,” wrote Neil Dutta, head of economics at Renaissance Macro Research. “The rise in quits is welcome since it indicates that workers remain confident about being able to find work.”

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