Pew Research Center is a nonpartisan fact tank that informs the public about the issues, attitudes and trends shaping America and the world. It does not take policy positions. The center conducts public opinion polling, demographic research, content analysis and other data-driven social science research. It studies US politics and policy; journalism and media; internet, science and technology; religion and public life; Hispanic trends; global attitudes and trends; and US social and demographic trends. All of the center’s reports are available at http://www. pewresearch. org/. Pew Research Center is a subsidiary of The Pew Charitable Trusts, its primary funder. This report was made possible by The Pew Charitable Trusts, which received support for the project from the Bill & Melinda Gates Foundation.