> 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/lastnmonth.md).

# LASTNMONTH

The **LASTNMONTH** function can be used to select data from a given measure for a specified number of months preceding the start of the current month. It should be used in conjunction with the SELECT clause and with an aggregate function like SUM or AVERAGE. 

## Syntax

```javascript
LASTNMONTH(number_of_months)
```

## Arguments

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

## Return value

Period Range.

## Example

```javascript
LASTNMONTH(15) 
//Returns data for the past 15 months preceding the start of the current month
```

<figure><img src="/files/mKbgYi8K1Ts53HwWVAFz" alt=""><figcaption><p>LASTNMONTH</p></figcaption></figure>


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