Electronics retailer Best Buy Co. (BBY - Get Report) posted better-than-expected earnings for the second quarter and raised its profit outlook for the full year but the stock tumbled in premarket trading after quarterly sales came up short.

Adjusted earnings of $1.08 a share were higher than 91 cents a year earlier and ahead of analysts' expectations of 99 cents.

Revenue was a touch below expectations for the period. The company posted sales of $9.5 billion, up from $9.4 billion last year. Analysts were expecting revenue of $9.6 billion.

For the third quarter, Best Buy said it expects revenue of $9.65 billion to $9.75 billion vs. analysts' forecasts of $9.78 billion, and same-store sales to rise 0.5% to 1.5%. Adjusted earnings were forecast at $1 to $1.05 a share.

The company said it expects full-year profit per share in the range $5.60 to $5.75, up from previous guidance of $5.45 to $5.65 a share.

The new guidance includes "our best estimate of the impact of recent announcements regarding tariffs on goods from China," said Best Buy Chief Financial Officer Matt Bilunas in a statement.

The stock was down 5.74% to $65.04 in premarket trading Thursday.

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Constable owns none of the securities listed in this story.