U.S. official says health insurance website improving

WASHINGTON (Reuters) - Round-the-clock efforts to improve the troubled federal website, HealthCare.gov, have increased performance across the site, a senior administration official said. Henry Chao, the deputy chief information officer at the Centers for Medicare and Medicaid Services, said in written testimony to a House of Representatives committee that the administration is preparing to expand the functionality of the site's consumer shopping subsidy estimation tool. The testimony was posted on Monday to the website of a House Energy and Commerce subcommittee that is scheduled to receive testimony from Chao at a hearing on Tuesday. (Reporting by David Morgan; Editing by Sandra Maler)