From events to metrics

Events record what happened. Metrics help teams understand the pattern.

A product might record that users viewed a form, submitted details, verified an email, or completed a workflow. Those records become useful when the team counts, combines, filters, compares, or calculates from them to answer a product question.

A metric is not the event itself. It is a measure created from event evidence.

Calculation patterns

Metrics are usually created from events in a few simple ways.

Pattern What it does Example
Count Counts how often something happened Users who triggered registration.form_submitted
Combine Uses two or more events together Users who submitted the form and verified email
Filter Narrows the population Completion rate for mobile users only
Compare Compares events, periods, or groups Completion before and after a workflow change
Calculate Creates a formula from event evidence registration.completed ÷ registration.form_viewed

The calculation is only useful when it matches the question.

Metric names are not definitions

“Registration completion rate” could mean several things:

  • completed registrations divided by registration form views
  • completed registrations divided by form submissions
  • users who verified email divided by users who started registration
  • users who accessed the product divided by users who clicked “create account”

Each version may be valid. Each answers a different question.

That is why a metric definition needs source events, formula, population, filters, exclusions, dimensions, and limitations. The name alone is not enough.

The same events can support different metrics

A set of events can support several useful measures.

For example, registration.form_submitted and registration.email_verified can help calculate:

  • number of submitted forms
  • number of verified emails
  • email verification rate
  • drop-off after form submission
  • time from form submission to email verification
  • email verification rate by device, entry point, or user type

This is one reason to design events carefully. A well-defined event can support multiple metrics. A vague or poorly timed event can create multiple arguments.

Metrics can hide behaviour

A metric summarises evidence, but it can also hide the detail a team needs.

A registration completion rate may fall from 60% to 50%. That tells the team something changed. It does not explain whether the issue is form abandonment, validation errors, email verification, first product access, or a change in the type of users entering the workflow.

A useful metric should point the team back to the behaviour, not replace it.

Practical rule

When creating a metric from events, write the definition before building the chart.

At minimum, define:

  • the product question
  • the workflow
  • the source events
  • the formula
  • the population included
  • filters and exclusions
  • useful dimensions
  • the decision or investigation the metric supports

If the team cannot define those things, it probably does not need a dashboard yet. It needs measurement design.

Key takeaway

Metrics are calculations with intent.

The event evidence gives the metric substance. The product question gives it a job.