Paper prices strengthened last summer but not enough for Boise Cascade Corp. to avoid a third straight quarter of red ink.

The paper manufacturer on Monday reported a $6.2 million loss for the July-September quarter, or 23 cents per share of common stock, on revenues $1.44 billion.

The loss was nearly four times greater than the $1.7 million, or 24 cents a share, reported a year ago on revenues of $1.36 billion. But Chairman George Harad took heart in the improvement over the second quarter when the red ink totaled $16.2 million, or 53 cents a share.

“The performance of the company’s paper business should continue to improve in the fourth quarter and beyond,” Harad said in a statement. “Paper markets have strengthened over the last several months, and operating rates for Boise Cascade’s key grades are high.”

Harad was at the helm when Boise Cascade ended 15 straight quarterly losses in late 1994 and kept the company in the black for 1-1/2 years. But with this summer’s loss, the company has now failed to post a profit in five of the last six quarters.