On this slide, the graph on the right shows an example of the 60mil (1.5 mm) testing where the trend of absorption (indicated by the gray curve) is expected to increase with higher frequencies. The reflection curve (red curve) will increases with frequencies and since it is based on S11 parameter testing, the closer the curve is to zero means more reflection. Note the testing is based on ASTM D-5568-01 standard. Also note that the left axis indicates dB and not dB/mm.