"That's a high salary for this position! Where did you come up with that figure?"If you said a figure that was too high, you might hear this question from the interviewer. This is not good because they would only ask this if the figure you stated was too high. So I would first justify the larger figure and explain that would consider a little less.
"I have three more years of experience that will help a lot. I also have a college degree that is not stated as a requirement. But if the figure is too high, I would consider something a little less."