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

# Historical Returns

The Historical Return model uses historical data from the selected time series returns to estimate expected return. The return for a given time series is calculated in [annualized discrete terms](/expected-risk/annualizing-volatility-and-return.md). 

### Missing Data

To account for missing or incomplete data, select “Use Maximum Likelihood Estimators.”

![Historical estimation options](/files/-MEyN0uTEvYfqJrHS1Fe)