The cane sugar refining segment of the sugar industry (SIC 2062) is composed of 29 refineries operated by 20 companies. Most refineries, though over 50 years old, have been modernized and operate at full capacity refining raw sugar--32 percent the total capacity. Estimated after-tax return on sales are about one percent for all sizes of liquid and crystalline refineries. Prices are controlled indirectly under the price competition from other sweeteners. Imposition of effluent limitations are not expected to raise prices. Potential refinery closures by 1977 due to the imposition of the effluent limitation guidelines are estimated to be from three to five refineries representing from six to eleven percent of total production. No additional closures by 1983 are expected.