What an amateur, the algorithm described here suffers from the same problem as keeping the running sum only in the other direction. It will stop working when th

What an amateur, the algorithm described here suffers from the same problem as keeping the running sum only in the other direction. It will stop working when the values you send it divided by the count are smaller than the precision of floats on your system... Actually depending on the values you give it it might preform a lot worse than the running sum version.