Is there a way to monitor the _average_ membrane potential of a group of neurons?

Hi all! As the title suggests, I am looking into a way to monitor the average membrane potential for a group of neurons. The problem I am facing is the large size of the network; it is very inefficient to record from all neurons and then average in post-processing.

I thought I could add a shared variable Vm to the group equations, but I ran into the problem of how to update it at every time step with the avg value I wanted. Then I thought I would add a network operation that calculates and stores the values separately, using numpy arrays. While this works, I was wondering if anyone knows of a way to make it into a monitor, so as to keep up with the rest of the code’s style.

Thanks for your time!