Salary: The total amount regularly paid or stipulated to be paid to an individual, before deductions, for personal services rendered while on the payroll of a business or organization.

Secondary school: An elementary/secondary school with one or more of grades 7-12 that does not have any grade lower than grade 7. For example, schools with grades 9-12, 7-9, 10-12, or 7-8 are classified as secondary.

Science literacy: An individual's scientific knowledge and use of that knowledge to identify questions, acquire new knowledge, explain scientific phenomena, and draw evidence-based conclusions about science-related issues. Science literacy also involves understanding of the characteristic features of science as a form of human knowledge and enquiry; awareness of how science and technology shape our material, intellectual, and cultural environments; and willingness to engage in science-related issues, with the ideas of science, as a reflective citizen.

Socioeconomic status (SES): A measure of an individual or family's relative economic and social ranking. See also supplemental note 1.

Special education schools: A public elementary/ secondary school that (1) focuses primarily on special education, including instruction for any of the following: hard of hearing, deaf, speech impaired, health impaired, orthopedically impaired, mentally retarded, seriously emotionally disturbed, multi-handicapped, visually handicapped, deaf and blind, and the learning disabled; and (2) adapts curriculum, materials, or instruction for students served.

Status dropout rate: The status dropout rate is a cumulative rate that estimates the proportion of young adults who are dropouts, regardless of when they dropped out. The numerator of the status dropout rate for any given year is the number of young adults ages 16-24 who, as of October of that year, had not completed high school and were not currently enrolled. The denominator is the total number of 16- to 24-year-olds in October of that same year.

STEM fields: Science, Technology, Engineering, and Mathematics (STEM) fields of study are collectively considered core technological underpinnings of an advanced society.