Ceridian ( CEN) rose 3.5% Thursday after agreeing tto sell the major portion of its retirement plan services recordkeeping and administration business to Newport Group of Heathrow, Fla. About1,100 companies for whom Ceridian was providing defined contribution and defined benefit retirement plan administration services will become customers of Newport, effective immediately. Ceridian will retain and continue to provide retirement plan administration services to its current total human resources outsourcing clients. The transaction is expected to close at the end of July. "We are very pleased to have reached this agreement with Newport because it allows us to continue offering retirement services through a strategic alliance with a proven leader in retirement plan solutions," the Minneapolis, Minn.-based company said. "It also enables us to focus our efforts on strengthening our core operations, positioning us for greater flexibility to meet the growing and changing needs of our customers." Shares rose 79 cents to $23.59.