Affected Event Count: Events Impacted by EMQ Issues

Affected Event Count shows the number of events impacted by a specific EMQ diagnostic issue, helping you understand the scale of data quality problems.

Formula

Affected Event Count = COUNT ( Events ) WHERE diagnostic_issue = active

Formula Components

Metric	Definition
Events	Total events sent via Conversions API
diagnostic_issue = active	Filters to events with a specific data quality problem flagged by Meta

Metadata
Type	Number
Data Source	Meta Ads
Aggregation	Count

Example

Your Purchase event has a diagnostic issue flagged for missing phone numbers:

Event Type	Total Events	Affected Events	Impact
Purchase	12,450	3,847	30.9% affected
AddToCart	45,200	8,104	17.9% affected
ViewContent	128,000	15,360	12.0% affected

How It Works

Meta’s Event Match Quality system scans your Conversions API events for data quality issues. Each diagnostic issue tracks how many events are impacted. Higher counts indicate a broader problem that affects more of your conversion data and may reduce attribution accuracy.

When to Use

Scenario	Action
Prioritizing fixes	Focus on diagnostics affecting the most events first
Measuring improvement	Track affected count over time after implementing fixes
Assessing impact	Understand how widespread a specific data issue is
Resource allocation	Allocate engineering time based on event volume affected

Metric	Relationship
Affected Events %	Percentage version of this metric
Diagnostics Count	Total number of active diagnostic issues

See all EMQ metrics →

Affected Events %Browser Dedupe Coverage

⌘I

​Formula

​Formula Components

​Example

​How It Works

​When to Use

​Related Metrics

Formula

Formula Components

Example

How It Works

When to Use

Related Metrics