> For the complete documentation index, see [llms.txt](https://excelhelp.windhamlabs.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://excelhelp.windhamlabs.com/functions/risk-models/historicalrisk.md).

# HISTORICALRISK

## Description

The following risk model estimates covariances based on equally-weighted historical observations.

## Syntax

The following describes the function signature for use in Microsoft Excel's formula bar.

```excel-formula
=HISTORICALRISK(type, assetReturns, dataPeriodicity)
```

### Input(s)

| Argument            | Description                                                                                                                                                                                    |
| ------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **type**            | <p>Required. Enumeration string to specify calculation type:<br>   "risk", "sigma", or "stdev"<br>   "correlation", "corr", or "rho", <br>   "covariance", "covar", or "cov"</p>               |
| **assetReturns**    | Required. Time series or matrix of asset returns.                                                                                                                                              |
| **dataPeriodicity** | <p>Optional. Periodicity of the data, used for annualization. If you do not enter the argument, it defaults to 1. <br><em>e.g. Daily = 255, Monthly = 12,  Yearly = 1, Quarterly = 4.</em></p> |

### Output(s)

Depending on the specified output *type*, the function will return the respective vector of risk estimates (annualized standard deviations), correlation matrix, or a covariance matrix.

## Example

![](/files/-ML9Ghswu8MmVLXqLHjY)

{% file src="/files/-ML9GlYdPtrnjCBL4Fos" %}
Example Workbook: HISTORICALRISK
{% endfile %}


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