What matters
The calculation needs an explicit cost scope and customer group. Keep media-only comparisons separate from analyses that include other acquisition costs, and document timing so the team understands which purchases are related to the measured effort.
Put it into practice
- Define included costs
- Define the customer group
- Document the matching period
An example in practice
A media report and a wider sales-cost review use different cost scopes. The team labels them rather than presenting the two figures as directly equivalent.
What to track
Defined acquisition costs divided by the defined customer count.