# What metric to use for calculating the average percent error?

Let's say that I have a model that counts target objects in images. In the first image, I have success $1/2$ and in the second image is $1/5.$

First image: Absolute error = $1$, percent error = $50\%$

Second Image: Absolute error = $4$, percent error = $80\%$

I want to calculate the average percent error for both of the images. Should I go with the total absolute errors and divide it by the total number of targets or should I calculate the avg of the two percent errors?