Hearing loss was first quantified as a percentage of remaining dynamic range

Evidence

Wegel and Fowler observed that hearing thresholds could be quantified as a percentage of the dynamic range at each frequency. They counted the number of logarithmic steps between the minimum and maximum audibility curves and then counted the number of steps between minimum audibility and the patient’s threshold. … Wegel and Fowler felt that plotting the data in this way better quantified how much dynamic range was left for a listener with impaired hearing. — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 95

Categorization

• XREF: This percentage-of-dynamic-range approach anticipates modern speech-in-noise measures of hearing handicap, where remaining usable range matters more than absolute threshold.