BUSINESS DIGEST
Companies United Airlines announced layoffs, salary cuts, fewer flights and other measures aimed at cutting operating expenses by $400 million a year. [ Page D1. ] Ford outdealed Honda to claim the best-selling car title. Ford's 409,751 Tauruses compared with 393,447 Accords sold in 1992. [ D1. ] Sales of domestically made cars and light trucks fell 1.5 percent in the final 10 days of 1992. [ D5. ]