Lawson Inc. said Tuesday its group net profit more than doubled during the first half of the current business year, thanks to the absence of huge restructuring costs booked last year.

Japan's No. 2 convenience chain said its group net profit for the March-August period rose 123.4 percent to 10.18 billion yen, though revenues were down 4.2 percent to 125.48 billion yen.

The chain closed 342 outlets during the first half of the previous business year, booking a one-time 15.2 billion yen charge for restructuring expenses.

In addition to an unusually cold summer, the firm blamed the revenue decline on the termination of high-price prepaid expressway cards sold at its outlets.

On March 1, sales of prepaid cards priced at 30,000 yen and 50,000 yen were halted due to a counterfeiting problem, cutting the chain's revenues by 8.9 billion yen.

Excluding the expressway card factor, sales at outlets that have been open for at least a year dropped 2 percent from a year earlier, it said.

But cost-cutting efforts helped the firm post a 1.9 percent increase in its group operating profit, which hit 21.07 billion yen.

The chain, whose number of outlets grew a net 86 to 7,711 during the period, has expanded its tieups with other companies; Lawson stores have been opened at post offices and hospitals, and at a bank.

Unlike rival Seven-Eleven, Lawson will not shift its merchandise focus toward originally developed products, which currently account for some 30 percent of the chain's total sales.