Wal-Mart Stores Inc's U.S. customers are still contending with delays in getting their tax refunds this year, with volume running about a third lower than normal, the discount chain's finance chief said.

Wal-Mart has cashed some $2.7 billion in tax refund checks at its U.S. stores so far this year, Chief Financial Officer Charles Holley said at an investor conference. At this point last year, that amount was about $4 billion.

Holley said that he expected tax refund volumes, which help drive sales at the retailer, to catch up during the quarter.

As of Feb. 21, when Wal-Mart announced quarterly results, it had cashed $1.7 billon in tax refund checks, compared to $3 billion a year earlier.

Federal tax refunds are arriving later than expected this year for some lower-income Americans due in part to closer scrutiny by the U.S. Internal Revenue Service of earned income tax credit claims, the IRS said last month.

The delays are largely responsible for a slow start to the current quarter, which began in February, the company said last month. Tax refund checks are a key source of revenue for retailers like Wal-Mart, as shoppers who held off on big purchases at the holidays get caught up.

The company expects sales at its U.S. stores open at least a year, or same-store sales, to be about flat during the current quarter. A year earlier, such sales rose 2.6 percent.