Low Traffic and cardinality

Low Traffic and Cardinality

What is Low Traffic?

"Low Traffic" in reports = cardinality overflow

When unique values exceed the limit for a variable, Adobe creates a "Low Traffic" bucket.

Cardinality limits

If you exceed the limit:

• New values are grouped into "Low Traffic"
• You lose visibility into individual values
• Reporting becomes aggregated

Example: Cardinality overflow

Day 1-29: You have 500 unique page names (fine, below limit)

Day 30: You add a dynamic page generator that creates 1M URLs like:

• /product/123
• /product/124
• /product/125... (1M variations)

Result: All 1M URLs grouped into "Low Traffic"

Problem: You can't see individual products anymore

How to prevent

1. Use summary pages

Instead of tracking 1M product pages individually, track:

• prop1 = "Product Page" (generic)
• eVar1 = Product ID (numeric, 10K unique)

Result: Low cardinality, good reporting

2. Truncate values

Instead of full URL, send summary:

// WRONG (high cardinality)
s.prop1 = window.location.href;

// RIGHT (low cardinality)
s.prop1 = "Product Page";

3. Group by category

Instead of individual values, group:

// WRONG (1000s of unique values)
s.eVar1 = sessionData.userEmail;

// RIGHT (5 categories)
s.eVar1 = userSegmentCategory; // "Premium", "Standard", "Free"

4. Monitor cardinality

Check monthly:

• Admin → Report Suite Usage
• See unique values per variable
• If approaching limit, reduce sources

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Next: Double counting