> For the complete documentation index, see [llms.txt](https://docs.usepylon.com/pylon-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.usepylon.com/pylon-docs/platform/custom-fields/field-history.md).

# Field History

### Overview

Field history tracks changes made to custom field values in Pylon, allowing you to view historical data and analyze trends over time. This is particularly valuable for monitoring key metrics like ARR, health scores, sentiment, and account engagement.

<figure><img src="/files/zIadvM9bcCLBPO3s8o2H" alt="" width="280"><figcaption></figcaption></figure>

### Formulas

Track field history using account formulas: `GetValue`, `GetValueRelative`, `QueryChange`, and `QueryChangePct`. These formulas let you fetch point-in-time values or calculate changes over time. Learn more about formulas here.

<figure><img src="/files/XwqUmO4wlAys0Sf16lFO" alt=""><figcaption></figcaption></figure>


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