semester system, has 12 academic departments, 11 research institutes and 33 on-campus majors, the most popular of which are economics, government, psychology, economics-accounting and international relations. However, as a member of the Claremont Colleges, students at CMC also have the option to study any major that is not offered at CMC given that one of the other colleges has such a major. A popular example is computer science, which is offered by both Harvey Mudd College and Pomona College. The student to faculty ratio is 8:1 with an average class size of 18. 85% of the classes have fewer than 19 students. The six-year graduation rate is 93.3%, and the freshman retention rate is 92.7%. Curriculum About one third of the classes students complete are general education requirements. These include a humanities seminar and a writing seminar their first year, three semesters of a foreign language or demonstrated proficiency, a mathematics or computer science course, one laboratory science course and three semesters of a P.E. course or two seasons on a sports team. In addition, students must complete at least two humanities courses and three social science courses, all in areas outside the student's major. All students must complete a senior thesis, which can be either one-semester in length or, to receive departmental honors, two semesters. Claremont McKenna's curricular emphasis is on its social sciences, particularly economics, government, international relations, and psychology. CMC also offers an Oxford-style tutorial Philosophy, Politics, and Economics major with two separate tracks of 14 students each. Other multi-disciplinary majors include management engineering, philosophy and public affairs, science and management, econ-accounting, biology-chemistry, and environment, economics, and politics (EEP). CMC also offers the Robert A. Day 4+1 BA/MBA, in which students receive both their BA from Claremont McKenna and their MBA from the Drucker School of Management at Claremont Graduate University in 5 years. Its most popular undergraduate majors, by 2021 graduates, were: Economics (90) Multi-/Interdisciplinary Studies (27) Political Science and Government (24) Computer Science (17) Experimental Psychology (16) International Relations and Affairs (16) CMC's science program is currently offered through the Keck Science Department of Claremont McKenna, Pitzer and Scripps Colleges. The Keck Science Department offers a double year-long introductory science class to allow more flexibility than the former 3 year-long introductory biology, chemistry and physics courses that most science majors must complete. In October 2018, CMC announced that it plans to withdraw from Keck to