Prevent Outlook from reformatting contact telephone numbers

[coffent]

Currently, Outlook reformats contact telephone numbers that I enter as

xxx xxx xxxx
to


(xxx) xxx-xxxx

In an earlier version of Outlook, I was able to prevent the reformatting, and numbers entered previously retain their un-reformatted form. However I can't find any way of preventing newly-entered phone numbers from being reformatted. Is there a way?