MIT admitted 8.2 percent of students who applied this year, marking the lowest ever acceptance rate in the history of the university. Stu Schmill, dean of admissions, said the Massachusetts Institute of Technology received 18,989 applicants and accepted 1,548. The admittance rate has been cut in half over the past decade. He said that another reason the admittance rate is at a record low is because the institute’s yield rates, or number of accepted students who choose to enroll, have been increasing. Last year, MIT retained 70 percent of accepted students, he said. To prevent over-enrollment, the institute accepted fewer students, and put about 4 percent of applicants on the waiting list.