> 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
Filters a range of data from the last 'n' days prior to the current date.
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
```
LASTNDAY
---
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