Has anyone figured out the MFD Range Indicator control for the CRJ700? As you push it, it goes from 640, 320, 160, 80, 40, 20, 10, 5 and 8. These should be the distance to the outer ring - Correct ?? Or am I completely misreading its function?

However, based on ranges on the Garmin GPS 500, they seem backwards to me. The 640 is more like 10 miles on the GPS; 320 = 20; 160 = 40; 80 = 80; 40 = 160; 20 = 320 and 10 = 640 miles. 5 and 8 do not seem to equate to anything. Is there any way to fix this in the guage script?
Thanks,
Roger