Gradient Noise node output range doesn't match docs

The Gradient Noise node doesn't output values in the [0;1]range like mentioned in the doc.

It seems more to be going from about -0.015 to a bit above 1.025 .

See the following image that shows the out of range values : 

Two possible outcomes to fix this :
1. Find the flaw in the noise function to have the output in the desired range
2. Remove the range mention in the doc. Or mention the real approximate range so users can remap or clamp it in their graphs.