Costco says sales for its fiscal second quarter climbed 8% to $24.34 billion, up from $22.51 billion in the same period a year ago, propelled by a 5% gain in same-store sales. And net income jumped 39% rose to $547 million, compared to $394 million in the same period. (The company received a $62 million tax benefit in the period, but even excluding that, income would have risen 23%.) In a conference call, a company executive says the sales were “very slightly” benefitted from higher gasoline prices, adding that average transaction price and frequency of shopping trips were up, as are renewal rates.