This publication is based on data from two annual federal surveys. Bachelor's and master's degree data and data on doctoral degrees in engineering technologies were collected from institutions of higher education by the Integrated Postsecondary Education Data System Completions Survey, conducted by the National Center for Education Statistics (NCES), U.S. Department of Education (ED). Data on research doctoral degrees in all fields except engineering technologies were collected by the Survey of Earned Doctorates (SED), a universe survey of individual doctorate recipients sponsored by the National Science Foundation (NSF) and five other federal agencies: the National Institutes of Health, ED, the U.S. Department of Agriculture, the National Endowment for the Humanities, and the National Aeronautics and Space Administration.

These data cover earned degrees conferred from 2002 to 2012 in the aggregate United States, which comprises the 50 states, the District of Columbia, and the U.S. territories and outlying areas (American Samoa, the former Canal Zone, Guam, the Northern Mariana Islands, Puerto Rico, the U.S. Virgin Islands, and the Trust Territory of the Pacific Islands). Degree data are compiled for a 12-month period, 1 July through 30 June of the following year. For convenience, degrees in a given July- June period are referred to by the year in which the period ended (e.g., 2012 means the 12-month period beginning 1 July 2011 and ending 30 June 2012).

The broad field category "engineering" excludes engineering technologies. Reports in this series published before 1995 included this field in engineering. The present classification makes trend data by race or ethnicity more consistent with the definition of science and engineering (S&E) used in other NSF reports. In this report, data on bachelor's, master's, and doctoral degrees in engineering technologies are provided separately in tables 27–29; for time series, the reader can add these data to "engineering" to have this field correspond to earlier data. Degrees in the health/medical sciences are also not included in totals for S&E fields but are provided as separate data tables (tables 30–32), as are data on first professional degrees (tables 33–35).

The time series for degree data may be affected by changes in definitions, instructions, and field classifications, including the introduction of new specialties. In this report, data for earlier years are presented as consistently as possible with the current field classification system, the 2010 Classification of Instructional Programs. See appendix B, "Classification of Fields of Study" for complete information on the field classifications used in this report, also see appendix A, "Technical Notes," for a discussion of the impacts of field classification changes to counts of bachelor's, master's, and doctorate degrees in six engineering fields.