An orthogonal cutting operation is being carried out in which uncut thickness is $0.010$ mm, cutting speed is $130$ m/min, rake angle is $15^{\circ}$ and width of cut is $6$ mm. It is observed that the chip thickness is $0.015$ mm, the cutting force is $60$ N and the thrust force is $25$ N. The ratio of friction energy to total energy is _______ (correct to two decimal places).