In 2010, Continental Airlines and United Airlines announced that they would merge and that the headquarters of the combined company would be in the Chicago Loop in Chicago. The airline has not stated how much of the of space that it leases in Continental Center I will be vacated. As of 2010 Continental had around 3,000 clerical and management workers in its Downtown Houston offices. According to Nicole Bradford of the "Houston Business Journal", some believe that the airline will vacate and leave thousands of square feet of space in Downtown Houston empty. As of 2010 Continental leases in Continental Center I, about 40% of the tower's office space. United has begun to move employees to a new operations center in the Willis Tower (former Sears Tower) and one thousand are expected by the end of 2010. As of September 2011 Continental continues to have employees at Continental Center I, which is now a former headquarters. About half of the existing employee base will remain in the building. As of September 2011 Continental continues to occupy space at Continental Center I, now a former headquarters, and another building. Half of the previous number of employees will work in Downtown Houston. Some job positions were eliminated. Some employees were transferred to Chicago.