> For the complete documentation index, see [llms.txt](https://docs.inforiver.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.inforiver.com/formula-syntax/time-intelligence-functions/lastnday.md).

# LASTNDAY

The **LASTNDAY** function can be used to select data from a given measure for a specified number of days preceding the current day. It should be used in conjunction with the SELECT statement and an aggregate function such as SUM or AVG. 

## Syntax

```javascript
LASTNDAY(number_of_days)
```

## Arguments

number\_of\_days – The number of preceding days for which data has to be fetched. Required.

## Return value

Period Range.

## Example

```javascript
LASTNDAY(45) 
//Returns data from the last 45 days preceding the current one
```

<figure><img src="/files/DbOUL0L7Poz3M28HNW55" alt=""><figcaption><p>LASTNDAY</p></figcaption></figure>


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