This breathing exercise will help to ground yourself as well as generally improving the movement of chi/energy throughout the whole body. It has a gentle but deep cleansing effect if used regularly.
Taoist Yoga is especially good for relaxation and to remove anxiety. It gives prompt, quick relief. However, the effects can be quite temporary. Therefore, special efforts must be made to prolong and deepen these results by subtle, attentive, repeated practice!.
The Taoist relaxation method is very simple: "Listen to your breathing." Nothing more is needed, except persistence and patience in such listening. If you do not persist, your attention will stray back into anxieties.