Deregulation enabled new companies to enter and created competition in wages between union and nonunion sectors of the industries. Until now, wages and employ in trucking, air carriers, and telecommunications. Airline deregulation had relatively little initial effect on mechanics' pay, but pilots' salaries fell between 3 and 11 percent, and salaries of flight attendants dropped from 11 to 18 percent. Mechanics would have alternative employment opportunities in their occupation in other industries, an advantage not enjoyed by pilots and flight attendants. Following deregulation in the trucking coverage of truckers by the National Master Freight Agreement industry. negotiated by the Teamsters and Trucking Management Inc. fell by two- thirds. Wages fell by 27 percent, and return on equity for unionized truck ing companies fell by 22 percent between 1977 and 1990 due to decreases in freight shipping rates. The effects of deregulation continue to occur in other industries.