> ## Documentation Index
> Fetch the complete documentation index at: https://docs.anlytic.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Lag

Returns the value from a previous row at a specified offset before the current row within a partition.

**Category:** `window`

**Syntax:**

```
Lag([column], offset)
```

**Returns:** `Same as input type`

**Context Filtering:** ✓ Yes

## Parameters

| Name     | Type      | Required | Description                                                                          |
| -------- | --------- | -------- | ------------------------------------------------------------------------------------ |
| `column` | `column`  | ✓ Yes    | The column to retrieve the previous value from                                       |
| `offset` | `integer` | ✗ No     | The number of rows before the current row to retrieve the value from. Defaults to 1. |

## Validation

* Minimum parameters: 1
* Maximum parameters: 2

## Examples

```
Lag([Sales])
```

Returns the sales value from the previous row (1 row back).

```
Lag([Price], 3)
```

Returns the price value from 3 rows before the current row.

```
Lag([Revenue], 7)
```

Returns the revenue from 7 days ago, useful for week-over-week comparisons.

## Related Functions

* [Lead](lead) - Returns value from following row
* [First](first) - Returns first value in partition
* [Last](last) - Returns last value in partition
* [RowNumber](rownumber) - Assigns sequential row numbers