> ## 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.

# MovingStdDev

Calculates the moving standard deviation of values within a specified window of rows relative to the current row.

**Category:** `window`

**Syntax:**

```
MovingStdDev([column], window_start, window_end)
```

**Returns:** `Float`

**Context Filtering:** ✓ Yes

## Parameters

| Name           | Type      | Required  | Description                                                                                        |
| -------------- | --------- | --------- | -------------------------------------------------------------------------------------------------- |
| `column`       | `column`  | ✓ Yes     | The numeric column to calculate moving standard deviation for                                      |
| `window_start` | `integer` | ✓ Yes     | The number of rows before the current row to include in the window (negative value)                |
| `window_end`   | ✗ No      | `integer` | The number of rows after the current row to include in the window (positive value). Defaults to 0. |

**Allowed Column Types for `column`:** INT, FLOAT, DECIMAL, NUMBER

## Validation

* Minimum parameters: 2
* Maximum parameters: 3

## Examples

```
MovingStdDev([Sales], -6, 0)
```

Returns the standard deviation of sales in a 7-day rolling window (current row and 6 previous rows).

```
MovingStdDev([Response_Time], -29, 0)
```

Calculates a 30-day moving standard deviation of response times, useful for tracking variability over time.

```
MovingStdDev([Stock_Returns], -19, 0)
```

Calculates a 20-day rolling volatility (standard deviation) for stock returns.

## Related Functions

* [CumulativeStdDev](cumulativestddev) - Calculates cumulative standard deviation from the first row
* [MovingVariance](movingvariance) - Calculates moving variance with a window
* [StDev](../aggregate/stdev) - Returns the overall standard deviation
* [MovingAvg](movingavg) - Calculates moving average with a window