# Review count change

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**Review count change:** How many reviews a listing gained since we last observed it.

## How we measure it

We subtract the earlier review count from the later one; the first observation of a listing has no change.

## What it is not

Reviews follow completed stays, so a rising count confirms a listing hosted someone. Not every guest leaves one, so it is a lower bound on stays, not a booking count.

## Where it appears in the data

Field names as the API returns them; each dataset's page in the API lists the field's type and unit.

- `review_delta` in dataset `airbnb_occupancy`

## Related

- [Short-term rental data: how we measure it](/methodology/short-term-rentals/)
- [All glossary terms](/glossary/)