  In this short report, we investigate the mutual information hidden in the
Parikh-Wilczek tunneling model of Hawking radiation for Kerr-Newman black
holes. By assuming the radiation as an optimization process, we discuss its
effect on time evolution of rotating (charged and uncharged) black holes. For
uncharged rotating black holes evaporating under the maximum mutual information
optimization, their scale invariant rotation parameter $a_*=a/M$ is almost
constant at the early stage but rapidly increase at the very last stage of the
evaluation process. The value of rotation parameter at the final state of
evaporation depends on the initial condition of the black hole. We also found
that the presence of electric charge can cause the black holes lose their
angular momentum more rapidly than they lose mass. The charged-rotating black
holes asymptotically approach a state which is described by $a_*= 0$ and $Q/M =
1$.
