docs-v2/content/flux/v0/stdlib/experimental/mean.md

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---
title: experimental.mean() function
description: >
`experimental.mean()` computes the mean or average of non-null values in the `_value` column
of each input table.
menu:
flux_v0_ref:
name: experimental.mean
parent: experimental
identifier: experimental/mean
weight: 101
flux/v0/tags: [transformations, aggregates]
introduced: 0.107.0
---
<!------------------------------------------------------------------------------
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------------------------------------------------------------------------------->
`experimental.mean()` computes the mean or average of non-null values in the `_value` column
of each input table.
Output tables contain a single row the with the calculated mean in the `_value` column.
##### Function type signature
```js
(<-tables: stream[{A with _value: float}]) => stream[{A with _value: float}]
```
{{% caption %}}
For more information, see [Function type signatures](/flux/v0/function-type-signatures/).
{{% /caption %}}
## Parameters
### tables
Input data. Default is piped-forward data (`<-`).
## Examples
### Calculate the average value of input tables
```js
import "experimental"
import "sampledata"
sampledata.float()
|> experimental.mean()
```
{{< expand-wrapper >}}
{{% expand "View example input and output" %}}
#### Input data
| _time | *tag | _value |
| -------------------- | ---- | ------- |
| 2021-01-01T00:00:00Z | t1 | -2.18 |
| 2021-01-01T00:00:10Z | t1 | 10.92 |
| 2021-01-01T00:00:20Z | t1 | 7.35 |
| 2021-01-01T00:00:30Z | t1 | 17.53 |
| 2021-01-01T00:00:40Z | t1 | 15.23 |
| 2021-01-01T00:00:50Z | t1 | 4.43 |
| _time | *tag | _value |
| -------------------- | ---- | ------- |
| 2021-01-01T00:00:00Z | t2 | 19.85 |
| 2021-01-01T00:00:10Z | t2 | 4.97 |
| 2021-01-01T00:00:20Z | t2 | -3.75 |
| 2021-01-01T00:00:30Z | t2 | 19.77 |
| 2021-01-01T00:00:40Z | t2 | 13.86 |
| 2021-01-01T00:00:50Z | t2 | 1.86 |
#### Output data
| *tag | _value |
| ---- | ------- |
| t1 | 8.88 |
| *tag | _value |
| ---- | ----------------- |
| t2 | 9.426666666666668 |
{{% /expand %}}
{{< /expand-wrapper >}}