# Drill Down Preview

The *Drill Down Preview* is a feature which is still in experimental stage. It shows you what to expect after the next drill down in a little chart next to your main visualization. Imagine it to be a signpost if the size of a value corresponds to the values it is made up.

It can be activated in the Review / Preview Menu:

![](https://3415705954-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F9tIV2XT53haGp6nlAPXL%2Fuploads%2Fgit-blob-13d50ff4ece8c44e3dd3a6fbd4cc6b411af1eb66%2Fimage.png?alt=media)

The Drill Down Preview visualizes the **sigma** (standard deviation) of the underlying values for an element in your chart as blue bars.

Here is an example:

![](https://3415705954-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F9tIV2XT53haGp6nlAPXL%2Fuploads%2Fgit-blob-a0392c3fb724638125566727f5e6312e1dec2697%2Fimage.png?alt=media)

In this case, the sizes of sigma correspond roughly with the sizes of the main waterfall chart. But let us have a look at another example:

![](https://3415705954-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F9tIV2XT53haGp6nlAPXL%2Fuploads%2Fgit-blob-67c48bc6d6f3b20d4ef90ea5a8785b4b8215f3e1%2Fimage.png?alt=media)

In this chart we can see, that the sigma for *Consumer* is significantly higher than the actual delta. If we expand the node, we immediately see why:

![](https://3415705954-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F9tIV2XT53haGp6nlAPXL%2Fuploads%2Fgit-blob-e6c21f3f6eec9fd750e289fe7d1e7e65c6da48d6%2Fimage.png?alt=media)

The volatility of the values is rather high, compared to the very small delta. When the underlying deltas are summed up, the result indicates a small change. But it hardly reflects, what happens below. This is, what the drill down preview is meant to visualize.