Time-decay Attribution

Measured as

Measure Time-decay Attribution with a fixed attribution window, conversion event, and spend basis before comparing campaigns or creative tests.

Misused when

• Using time-decay without checking conversion lag patterns.
• Comparing results across models without aligning windows.

Operator takeaway

• Often better than linear when buying cycles are short and tracking is clean.
• Still biased for retargeting and branded search in many accounts.
• Keep the same decay rule so trends remain comparable.
• Use Time-decay Attribution only inside a stable attribution rule, conversion definition, and time window so campaign comparisons stay honest.
• If performance changes, check whether the metric moved for a real business reason or because the measurement setup changed underneath you.

Next decision

• Read Attribution vs incrementality: what to trust, when, and how to test if the decision depends on interpretation, policy, or trade-offs beyond the raw formula.
• Decide which report owns Time-decay Attribution before comparing campaigns, channels, or creative tests.