# LASTNDAY

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

## 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

Range of data.

## Example

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

<figure><img src="https://github.com/lumelinc/PowerTableDocs/blob/main/.gitbook/assets/image%20(448).png" alt=""><figcaption><p>LASTNDAY</p></figcaption></figure>


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