You should change it to use the dB scale, IMO. 0dB is reference level. I don't know if there's any correlation with your receiver's 0-100 scale or not (on some brands, 82=0dB) but IMO since the receiver actually operates and does its calibration using the dB scale (which actually means something specific -- 75dB SPL at the calibration mic using the receiver-generated pink noise which is itself generated at -30dB), seeing your volume setting in decibels above or below reference is useful.
Knowing that 1dB is a "barely audible change" while 10dB is "twice/half as loud" gives the dB scale some context. A volume setting of -20 (20dB below reference, or only a quarter as loud) can be interpreted more meaningfully than "50 on a scale of 100" because it's not really half of anything.