In this paper, an analysis of the experimental results on the impulse behaviour of grounding electrodes is presented. The parameters used for analyzing transient performance are reviewed and differences highlighted based on test data. The analysis is extended to (i) quantify the effect of impulse shape, (ii) quantify the effect of electrode length, (iii) compare low-frequency and impulse performance, and relate the impulse performance to high frequency performance. A generalized impulse coefficient is introduced to help elucidate the differences between different parameters used for the analysis of impulse test results on ground electrodes.