SEATTLE — Shares of Costco Wholesale Corp. soared yesterday after the warehouse club retailer reported a 5 percent jump in its fiscal fourth-quarter earnings, driven by a rebound in same-store sales growth, cost-cutting and a tighter returns policy for electronics.

The company also expressed optimism about fiscal 2008, saying earnings per share for the full year may come in higher than current Wall Street estimates.

Net income for the 16 weeks ended Sept. 2 rose to $372.4 million, or 83 cents per share, compared with $355.6 million, or 75 cents per share, a year earlier. Results were hurt by a one-time charge of $35.8 million, or 8 cents per share, reflecting a change in accounting for deferred membership-fee revenue.

Excluding the charge, earnings were $408.2 million, or 91 cents per share, well above the 83 cents consensus estimate of analysts polled by Thomson Financial.

Quarterly revenue grew 3 percent to $20.48 billion from $19.88 billion, missing Wall Street's estimate of $20.73 billion.

Same-store sales, a key indicator of a retailer's performance, rose 5 percent during the quarter. The increase for September was 6 percent, up sharply from August, when same-store sales grew by only 2 percent.

"I think there was some relief that they did rebound," said Dan Geiman, an analyst with McAdams Wright Ragen.

Shares of the Issaquah, Wash.-based company rose $5.82, or 9.19 percent, to close at $69.13 yesterday. Shares had glanced up to a 52-week high of $69.95 earlier in the day.

Costco for years has talked about lowering its costs, but hasn't delivered enough to please most analysts. Higher profit margins in core merchandise in the latest quarter showed that the company is starting to deliver on its promise, said Robert Toomey, an analyst with E.K. Riley Investments.

"This was kind of a breakout quarter ... for gross margin," Toomey said. "Investors, I think, are just more optimistic that the gross margin improvement is sustainable."

In March, Costco reined in its return policy on televisions, computers and other consumer electronics, giving customers a 90-day window to return the items. The previous unlimited time to make returns was abused by some customers, chief financial officer Richard Galanti said.

Cash reserves for returned items increased in the fourth quarter. Galanti attributed the increase mostly to the return-policy change, and said the company expects those reserves to continue increasing.

For fiscal year 2007, earnings dipped to $1.08 billion, or $2.37 per share, from $1.1 billion, or $2.30 per share, a year earlier. Sales rose to $64.4 billion, up 7 percent, from $60.15 billion in the previous year.

For fiscal 2008, Galanti said, the company projects earnings per share of between $2.81 and $3. Wall Street's consensus estimate is $2.91.

Costco operates 520 warehouses worldwide, including 385 in the U.S. and Puerto Rico. The company opened 31 new stores in fiscal 2007 and plans to open 31 to 36 new warehouses in fiscal 2008.