# forge.ta.stdev

```python
forge.ta.stdev(source: ArrayLike, period: int = 20, method: str = 'sma') -> np.ndarray
```

Standard deviation of the last ``period`` values around their moving average at this bar.

``method`` names the average: ``sma`` (the population deviation), ``ema``, ``smma`` or
``lwma``. The divisor is ``period``, not ``period - 1``.

Since Forge API 1.