A measurement plan is a document that, before analytics is deployed, sets out what will be measured, why and how. Without it, the usual situation arises where events are added gradually according to whoever needed what, and after a year no one knows what each figure means or whether it can be compared with the previous year. The plan contains business goals, indicators derived from them, a list of events with a precise definition and triggering condition, the parameters sent with each event, and a responsible person. Add also what is deliberately not measured, so the team does not keep returning to it. Keep the plan alive, date every change, and go through it again for major changes to the website. It is the cheapest insurance against data that cannot be trusted.
See also: Data quality in analytics, Data dictionary, Event tracking.
