# 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](https://wpahelp.windhamlabs.com/expected-risk/annualizing-volatility-and-return). 

### Missing Data

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

![Historical estimation options](https://2662147689-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-MEd8w0azNaE8v7NnoDC%2F-MEyM-J7QW-XolxfY2kG%2F-MEyN0uTEvYfqJrHS1Fe%2Fimage.png?alt=media\&token=7b641884-7d64-48d0-93b4-1661e2eec6d0)