In the present report some numerical results on the evolution equation of microvoids under quasi-static simplification (without consideration of inertial effect) are given in terms of the increasing rate of porosity versus external stress at different damage levels and in various damage stages at different material viscosities. (In other words, for different strain rates). Some results for the differential equation of the dynamic evolution of microvoids in ductile materials were respectively developed by Cortes [3] and Zheng [5] by different means as mentioned in the above section. Here we introduce the expression for the increasing rate of porosity under quasi-static approximation as [6]