We study discrete spectrum in spectral gaps of an elliptic periodic second order
differential operator in L2(ℝd)
perturbed by a decaying potential. It is assumed that a perturbation is nonnegative and
has a power-like behavior at infinity. We find asymptotics in the large coupling constant
limit for the number of eigenvalues of the perturbed operator that have crossed a given
point inside the gap or the edge of the gap. The corresponding asymptotics is power-like
and depends on the observation point.