I like to set grades in the course based on points, not percentages. This allows me to adjust values based on a mean of how the top 5 students in the course are performing (adjusts for a more/less difficult exam without "curving" it). If I do this by percentage, then it appears that I'm moving the bar. When I do this by points, it has worked well for me in the past. I don't see how to set up a points-based grading scheme.