Key points are not available for this paper at this time.
Abstract Various indicators of relative change (or difference) are considered. It is shown that the log change defined by log e (y/x) is the only symmetric, additive, and normed indicator of relative change. It is proposed that the values of the log change in percent, 100 log e (y/x), be denoted by the symbol L%, the log percentage. It is hoped that the symmetric and additive log percentages will gradually replace the ordinary asymmetric and nonadditive percentages.
Törnqvist et al. (Fri,) studied this question.