The data present the speed-up factors for the FEDM code and the commercial software package COMSOL Multiphysics® obtained for the streamer benchmark case. Note that simulations were performed for the early phase, until 500 ps. Note that the Newton-based nonlinear solver was used for the calculations in both cases. For the best overall performance, FEDM uses MUMPS, and COMSOL uses Pardiso as the direct solver. The data are presented in a table, where the first column is the number of physical cores, the second column is the speed-up of FEDM, and the third one is the speed-up of COMSOL.