> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sourcemedium.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Understanding your Contribution Margin

> How contribution margin is calculated, which variable costs it includes, and common validation steps

Contribution margin extends gross profit by including additional variable costs that scale with demand (for example, marketing spend).

## What it represents

Contribution margin answers: “After variable costs, how much do we have left to cover fixed costs and profit?”

Depending on your definition, it may include:

* Gross profit components (COGS + fulfillment + fees, etc.)
* Marketing spend (paid media + other variable acquisition costs)
* Other variable operating expenses (if modeled)

## Where to look in SourceMedium

* Marketing spend: [`rpt_ad_performance_daily`](/data-activation/data-tables/sm_transformed_v2/rpt_ad_performance_daily) (and/or configuration sheet spend inputs)
* Blended order profitability: [`obt_orders`](/data-activation/data-tables/sm_transformed_v2/obt_orders)

## Troubleshooting

If contribution margin is unexpected:

* Confirm which spend sources are included (integrations vs config sheet)
* Confirm refunds/cancellations and the revenue definition used