How to turn off TODO state logging globally?

[Bahodir Mansurov]

Hi,

I have set ~org-log-done~ to ~nil~, but whenever I change state of a
repeated task, I see something like this inserted in the body of the
task:

> - State "DONE"       from "TODO"       [2020-06-07 Sun 10:00]

As far as I know, I can turn off this kind of logging individually for
each TODO item or for each file using a property. But how can I do so
for all org files by default?

-- 
Thanks,
Bahodir