For each instance,
the gaps concern the best solution of 5–10 runs, except for the
metaheuristics TS, GRASP + PR, MAjPM, SALRP and VND, which
were evaluated using a single run by their designers. The running
times indicate the average duration per run. The computers and
programming languages used are so disparate that scaled times
for one reference computer would not be pertinent. We simply
indicate the computer used and its clock speed in gigahertz. Numbers
in boldface emphasize the best indicators