An aggregation type defined how several values for the same metric (each
with different tags) get merged into one value. Notice that these only get
called when there is at least one value to aggregate. The Natural type uses
the + operation defined on the MetricValue
An aggregation type defined how several values for the same metric (each with different tags) get merged into one value. Notice that these only get called when there is at least one value to aggregate. The Natural type uses the + operation defined on the MetricValue