ROAS
Return on ad spend (ROAS) relates a campaign's attributed revenue to its cost.
A ROAS of 3 means every euro invested brought in three euros of revenue. Whether the campaign made a profit only shows in the ROI, because it accounts for cost of goods and shipping. ROAS also requires attributing revenue, for example via discount codes or tracking links.
Calculation
Example: A campaign costs €5,000 and brings in €15,000 of attributed revenue. The ROAS is €15,000 ÷ €5,000 = 3.