Skip all navigation and go to page content.
Warning symbol Newer information is available


Science and Engineering Indicators and other titles published by the National Center for Science and Engineering Statistics (NCSES) are works of the U.S. federal government and carry no claim to copyright. Thus, material from these reports may be freely used as in the public domain. We do request that use of work from any of these reports be credited, and we appreciate voluntary reporting of its use. When possible, we would appreciate being notified when work that cites our sources is published.

Apple and the Apple logo are trademarks of Apple Inc., registered in the U.S. and other countries. App Store is a service mark of Apple Inc.