WHOLE_ELEMENT Stress

Hello, I am currently perferoming some simulations with Abaqus.
The problem is, I'd like to get an approximate stress (S11, S22, S33, S12, S13, S23) for each Element in a special Set. Ist there any option to retain this information for the "WHOLE_ELEMENT" from Abaqus or do I have to use the Integration Points and calculate the average by myself?

I am using C3D20 Elements.

Thanks in advance