Degreeing a Cam Shaft

Hey, not to get in the middle of the mud slinging but I have a question.
When do you read the peak on a ramp?
By that I mean, right when it reaches the peak, when it's at the peak or right when the indicator starts back down. On my experience there seems to be a few degrees when the lifter hits the side, top and back side of the lobe.
What do you guys measure, or how do you call the number?