Grade inflation

NYT blog by Catherine Rampell shows how dramatically grade distributions have changed at over 200 colleges and universities.  In 1960, 15% of all grades were A's, which rose to 31% by 1988 and 43% by 2008.  B's held their own, but the odds of getting a C have plummeted, dropping from 35% to 15% between 1960 and 2008. 

Rampell shows that grade inflation varies across different types of campuses.  Private schools have had more inflation than public schools; a private school student has an 86% chance of getting an A or B in any given class.  Grades are lower in Southern schools and schools with large engineering and science enrollments. 

Why have grades risen so much? Hard to argue that students are smarter (the trend on SAT scores is flat at best) or working harder (surveys actually indicate they are studying less).  No doubt some profs gave out higher grades in the late 1960s and early 1970s to keep folks like yours truly from getting drafted and sent to Vietnam.  But the Vietnam War was over in 1975 and this trend is continuing.  Another theory is that student evaluations are more likely to be used to evaluate faculty for tenure and raises, so faculty "buy" higher evals by giving higher grades.  I am not sure I buy that explanation either; some of the toughest graders in the Jenkins MBA program get the highest student evals.