At PermaU there is quite a bit of pressure in regards to D/F/withdrawal rates. In my department, the DFW rate is about 30% (so 30% of a class gets a D, F, or withdraws by the end of the term). When a class doesn't meet this number, eyebrows are raised. Is the professor too easy? It couldn't possibly be that the class was just better than average, right?
I maintain my standards from semester to semester. I do not believe in curving. The first exam average was an 80% (B-). The latest exam had an average of a 75% (C). These are, in my opinion, fairly high. Despite this, my DFW rate right now is right at 25%. With still another half of the semester to go, this percentage will likely go up. So this semester, I would guess I am on track for a 35-40% DFW rate.
My department maintains that the national DFW rate is between 50 and 60%. I find this insanely high, but it is likely that I am just out of touch. Could it be that the DFW rate really is that high in the sciences? Do you feel pressure to keep a certain average in your classes?