NEW YORK/WASHINGTON (Reuters) – Companies that provide the U.S. government with services ranging from air traffic management and data analytics to janitors and trainers for military dolphins are increasingly trying to find buyers for those businesses as cuts in public spending erode profit margins. Showing growing impatience with a declining sector, Lockheed Martin Corp (LMT.N) said earlier this week that it plans to sell or spin off information technology and services businesses that generate $6 billion a year in revenue.