> For the complete documentation index, see [llms.txt](https://docs.unsub.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.unsub.org/troubleshooting/how-do-you-calculate-the-open-access-portion-of-the-forecast.md).

# How do you calculate the open access portion of the forecast?

Data we use to calculate the open access portion of your Unsub forecast comes from our other product [OpenAlex](https://docs.openalex.org/). 

The calculation of the open access portion is not based just on whether a journal is open access or not, or how many articles in the journal are open access. It’s based on readership information. Of the articles that people actually visited, what percent of those are open access. To put this in concrete terms, if there’s a journal with 100 articles in it, and people only read 1 paper, it’s essentially a toll access journal.