906 ET - Taco Bell's same-store sales are down 2% in the U.S. so far this quarter, Yum Brands CFO Ranjith Roy says on a call with analysts Thursday. The chain's sales have been hurt in recent weeks by a multi-state cyclospora outbreak, which has been linked back to iceberg lettuce served at some of Taco Bell's locations. Taco Bell saw the largest sales impact from the cyclospora outbreak over the weekend of July 18, according to Roy. "It is early days, but in the subsequent weeks, sales declines have moderated materially and we are seeing steady improvement in day-over-day sales trends," he says. Shares of Yum Brands climb 4% premarket after reporting its 2Q profit more than doubled.