Average filaments from the center-side NEF (upper set of panels), limb-side NEF (middle panels) and CEF (lower panels) region. Subplots, that is, the set of five panels depicting filaments of a particular penumbral region, are in the same format as plots in Fig. 7. The head of CEF filament appears located on the right, while the NEF filaments are plotted with their heads on the left, that is, the filaments are plotted such that the part closer to the umbra is on the left for all three cases.