Calculating EPS? events.filtered / duration_in_millis is incorrect

Hello All,
I would like to calculate my events per second for logstash.
Currently I'm grabbing data via the logstash API but when I calculate the EPS it doesn't match up to what the 'metrics' logstash filter is reporting. (I had to use metrics due to this issue and said EPS).

{
  "out": 369050,
  "queue_push_duration_in_millis": 1566096,
  "filtered": 369050,
  "in": 377057,
  "duration_in_millis": 5541992
}

Using the above data from the API (.pipelines.dev.events) I would calculate EPS as $out / ($duration_in_millis / 1000) = 66.5

Now the only way this can be correct is if 66.5 needs to be multiplied by pipeline.workers.

Is that correct? Or have I gone way off tact here?

My testing shows that it must need to be multiplied by worker_count.

Annoyingly the longer the pipeline is up the more "averaged" the statistic becomes... Any workarounds in regards to that?