# Consolidated Reporting vs. Consolidated Inventory Reporting

Generally, mediators return two types of reports, waterfall reports, combined into the **Consolidated Reporting Table** and Inventory Reports known to us as **Consolidated Inventory Reporting.**

What's the difference?

* **Consolidated Reporting** shows demand source and placement information, but does not merge with ad requests.
* **Inventory Reporting** shows ad requests, which don't merge 1:1 with ad networks or placement information.

### **Why are there two types of reports?**

Simply put, it’s not possible to tie a single ad request to multiple ad delivery attempts through a waterfall. 

Think of it this way, a single ad request is sent to your mediator, it travels through 6 ad units before being filled. Which line item owns that request? Is it correct to assign 0 to the other line items? What do you do in the case of a lost (unanswered) attempt?

### **How to use each report**

* Consolidated Reporting is most commonly used to determine network & placement performance. 
* Consolidated Inventory Reporting is good for monitoring overall fill rates-- it powers our App Performance Page -- and is uniquely useful for the metric of Revenue per Thousand Ad Requests (Rev per AdReq) which shows the revenue generated by total device impression requests and can often be a more useful metric than CPM to judge performance.

![](https://336314087-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FaO8orL32xNzJW4MhnNef%2Fuploads%2F54xqRMrWOb65bzwJUVw0%2Fimage.png?alt=media\&token=d57fbed7-c23f-4df6-ae20-b4c4643a797a)