⚡ Tier 2 - ImportantID: mer
Marketing Efficiency Ratio (MER)
Blended ROAS across all marketing spend
In Simple Words (Zero Jargon):
Total business revenue divided by total ad spend across all channels combined.
Official Mathematical Equation
Total Revenue ÷ Total Marketing Spend (all channels combined)
Why It Is Critical
MER is the blended ROAS for the entire business - it looks at total revenue divided by total marketing spend across every channel simultaneously. Unlike platform-reported ROAS (which is notoriously over-inflated due to attribution overlap), MER is calculated from your own financial data and cannot be gamed by any platform's attribution model.
Strategic Rules of Thumb & Execution Playbook
- Track MER weekly using actual revenue from your finance system, not platform-reported revenue.
- Use MER as a sanity check against the ROAS numbers each platform claims. If all platforms report 4x ROAS but your MER is 2.1x, attribution overlap is overstating every channel.
- Set a target MER floor below which you reduce total spend, and a target MER ceiling above which you feel comfortable increasing budget.
What You Get: The single most honest measure of marketing efficiency at the business level - immune to platform attribution inflation.