[Yandex Cloud documentation](../../index.md) > [Yandex DataLens](../index.md) > Calculated fields > Function reference > Aggregate functions > STDEV

# STDEV



#### Syntax {#syntax}

{% list tabs %}

- Standard

  ```
  STDEV( value )
  ```

- Extended

  ```
  STDEV( value
         [ FIXED ... | INCLUDE ... | EXCLUDE ... ]
         [ BEFORE FILTER BY ... ]
       )
  ```

  More info:
  - [FIXED, INCLUDE, EXCLUDE](aggregation-functions.md#syntax-lod)
  - [BEFORE FILTER BY](aggregation-functions.md#syntax-before-filter-by)

{% endlist %}

#### Description {#description}
Returns the statistical [standard deviation](https://en.wikipedia.org/wiki/Standard_deviation) of all values in the expression based on a selection from the population.

**Argument types:**
- `value` — `Fractional number | Integer`


**Return type**: `Fractional number`

#### Example {#examples}




Source data

| **Date**     | **Temperature**   |
|:-------------|:------------------|
| `2019-03-01` | `5.00`            |
| `2019-03-02` | `0.00`            |
| `2019-03-03` | `-3.00`           |
| `2019-03-04` | `1.00`            |
| `2019-03-05` | `4.00`            |
| `2019-03-06` | `5.00`            |
| `2019-03-07` | `1.00`            |
| `2019-03-08` | `-6.00`           |
| `2019-03-09` | `-6.00`           |
| `2019-03-10` | `-4.00`           |
| `2019-03-11` | `-2.00`           |
| `2019-03-12` | `0.00`            |

Formulas:

- **Temperature SD**: `STDEV([Temperature])` .


Result

| **Temperature SD**   |
|:---------------------|
| `3.90`               |




#### Data source support {#data-source-support}

`ClickHouse 21.8`, `Files`, `Google Sheets`, `Microsoft SQL Server 2017 (14.0)`, `MySQL 5.7`, `Oracle Database 12c (12.1)`, `PostgreSQL 9.3`, `Trino`, `Yandex Documents`, `YDB`.