I am looking the equivalent of custom metrics in GA. The custom variables in PiwikPro seem more akin to custom dimensions in GA. But I would need an additional field (which would only be integers) that could be summed/averaged/other simple math function on a list of numbers.
Is there a function to declare them like for custom dimensions?
For example: “setCustomMetricValue”, metricID, “metricValue”
(I am using GTM to send the data)