The College Board, the nonprofit group that owns the SAT, announced today that the average combined scores on the exam's mathematics and critical-reading sections for the high-school class that graduated in 2007 declined by four points from the previous year, to its lowest level in nearly a decade. Average scores on the math section fell three points, to 515, and reading scores fell one point, to 502, out of a possible 800 points. A record 1.5 million students took the exam. Last year the combined scores on the SAT dipped by seven points, the biggest one-year drop since 1975. The College Board attributed that decline, in part, to a fall in the number of students who had taken the exam more than once.