The mean round-trip time is found to be 2.12 ns for the adaptive scheme, i.e. nearly 20% less that that obtained (2.68 ns) with the standard HREM scaling. Concerning the variance S (Eq. 6) i.e. the mean deviation of the time spent on any given node/state by each walker with respect to the ideal fraction of 1/12, we observe an increase when using the adaptive scheme as already noticed for the case of compound 1 (see Table ).