The Turkish arm of US snack giant Frito Lay, Frito Lay Turkey, has reported that its latest advertising campaign, launched earlier this month, has so far boosted sales by 40%. The campaign is to last until March 2002. Frito Lay Turkey, which producers and distributes the Ruffles, Doritos, Cheetos and Lay snack brands, currently holds a 75% stake in the domestic market.