What is a typical example of a circular reference in a financial model and how is it resolved?

• A. Revenue depends on headcount, which depends on revenue; resolve by separating drivers into independent schedules.
• B. Revenue depends on marketing spend; resolve by eliminating headcount.
• C. Headcount depends on revenue but not vice versa; no action needed.
• D. Revenue depends on revenue; impossible; ignore.

Answer: (B)

Circular references happen when outputs loop back to become inputs, so the model ends up in a feedback chain that prevents a single solution. A classic example is revenue that depends on headcount, while headcount itself is driven by revenue, creating a loop. The way to resolve this is by breaking the chain so one driver is no longer fed by the other—often by making one driver independent or by placing it on a separate schedule with fixed assumptions.

The option that describes breaking the cycle by removing a driving factor—eliminating headcount—best illustrates this idea. By removing the headcount dependency from the loop, you stop the reciprocal calculation and allow the model to converge. In practice, analysts achieve this by fixing certain drivers as independent inputs or by splitting drivers into separate schedules so they no longer feed back into each other.