Comprehensive records of all 1977 high school seniors who registered for the College Entrance Examination Board's Admissions Testing Program (ATP) before March of their senior year are analyzed in this national ATP summary report. Highlights include the fact that the average Scholastic Aptitude Test (SAT) scores of the 1977 seniors dropped 2 points in the verbal section from 431 to 429; and that the mathematics scores also declined, from 472 to 470. Average scores on all achievement tests declined from 538 in 1976 to 533 in 1977; some of this decline may be attributed to the English Composition Test scores, which dropped from 532 to 516. The number of women taking the SAT exceeded the number of men for the third consecutive year. Sixteen percent of those taking the SAT belonged to an ethnic minority; this percentage has increased for the second consecutive year. Three-fourths of the students were in the highest two-fifths of their high school class; their latest grade point average was 3.11, down from 3.12 in 1976. Health and medical-related fields still ranked first among intended areas of study for women; engineering remained the most popular choice for men. Parental income was found to have increased at a rate nearing that of inflation. (Author/MV)