> ## Knowledge Base Index
> Fetch the complete knowledge base index at: https://support.haddock.app/sitemap.xml
> Use this file to discover available pages before exploring further.
> Pure-Markdown content can be obtained by appending a '.md' suffix to the content URLs listed in the sitemap (without the trailing slash).

# Products without a reference price

The **reference price** of a product is generated by default by calculating the **weighted average of the last 12 months.**

You can find this calculation by clicking a product, going to **Settings**, and within **Prices** you can see how this reference price was calculated.

![](https://storage.googleapis.com/helpdesk-haddock-images/products/products-without-a-reference-price/images/01-products-without-a-reference-price.png)

🔑 If it is an **old product** that **has not been bought again**, it will appear without a reference price because the weighted average cannot be calculated.

We recommend uploading documents that include this product so the calculation can be made or, if you do not have any new purchases of the same product but still want to see a reference price, select the **Last purchase price** option.