Renaming Row Header categorised as Date Hierarchy in Matrix Visualisation

Hi, everyone!

Any ideas how to rename Row Header in Matrix Visualisation? It's about Date Hierarchy and I am wondering how could I rename "Year" in other language, for example German "Jahr". Changing application language in Options > Regional Settings didn't help. Column "Date" automatically "splits" in categories named "Year", "Month" etc. (not "Jahr", "Monat" etc.").

Thank you in advance!