MUSCATINE, Iowa (April 25)—Bandag Inc., feeling the effects of a sluggish global economy, suffered a 51.5-percent drop in operating earnings and a 6-percent decline in sales in the first quarter. The company faces an uncertain near-term future, said Martin G. Carver, Bandag chairman and CEO, because of rising energy prices, which impact both Bandag's raw material prices and the operating costs of its trucking customers. Bandag's net income before required accounting changes fell 47 percent to $1.22 million. Including the accounting change—which relates to impairment of goodwill—the net result fell $46 million into the red. Sales fell to $192.5 million, and the pretax operating profit was $1.94 million.