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Just starting on this, not for merging yet, but feedback welcome.
I was on the fence about measurement/metric so I googled around. The consensus that I found was that people considered "Measurement" to be the raw data and "Metric" to be derived from two or more measurements. For example, measuring the number of errors is a measurement but calculating the error rate (`error count / request count`) is a metric.

https://www.linkedin.com/groups/Metrics-vs-Measurement-3774402.S.135476549

I think "measurement" is a good naming choice. :+1: