" U.S. airports are important contributors to the U.S. economy, providing mobility for people and goods both domestically and internationally and often contributing to the economic success of the communities served. Since 2007 when GAO last reported on airport funding and its sufficiency to meet planned development of airport infrastructure, there have been significant changes in the aviation industry. During this time, federal support for airport development has declined. As deliberations begin in advance of FAA's reauthorization in 2015, Congress will consider the most appropriate type, level, and distribution of federal support for development of the national airport system. This testimony discusses trends in (1) aviation activity at airports since 2007, (2) costs of airports' planned development, and (3) federal funding and airport revenues that may be available to finance development costs. This testimony is based on previous GAO reports on aviation from June 2007 through June 2014, updated through June 2014 with interviews with key FAA and trade association officials and FAA airport funding data from 2005-2013. GAO shared the information it used to prepare this statement with FAA and incorporated its comments as"