Evolution of the measured break frequencies for the eight optical to radio SEDs for the GRB 100418A afterglow. The solid lines represent the expected theoretical evolution for a wind environment during fast (< 600 ks) and slow (> 600 ks) cooling. The coloured dashed lines represent the best power-law fits to the measured temporal evolution (open data points were left out from the fit). The horizontal dashed lines show the mean frequencies of our data (X-ray, optical, sub-millimetre, radio).