A measure of the number of Americans seeking unemployment benefits surged last week, although the figures may have been distorted by seasonal factors.

The Labor Department says applications rose by 34,000 to a seasonally adjusted 386,000. The increase reversed a big drop from the previous week.

Economists view the recent numbers with skepticism, noting that the government struggles to adjust claims figures to reflect temporary summertime layoffs in the auto industry. Many automakers are foregoing the typical shutdowns because stronger sales have kept plants busier.

The less volatile four-week average fell by 1,500 to 375,500.

Economists say the seasonal distortions may last a few weeks, making the figures difficult to analyze.

When applications fall below 375,000, it typically suggests hiring is strong enough to pull the unemployment rate down.

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