MCI capped its writedown at $550 million.

MCI Communications had announced this month that the big charge against its fourth-quarter profits could go as high as $700 million. In refining that estimate, the long-distance carrier’s chief financial officer, William E. Conway Jr., told Dow Jones News Service that more than half of the asset writedown would be related to satellite communications equipment, including assets acquired last February in the purchase of Satellite Business Systems. The charge will be partly offset by gains from MCI’s antitrust settlement with the former Bell System.