I was the Yank during my time in Sheffield and it was fine. Some of our Southern brothers may not prefer it. Why:
From Wikipedia's entry on "yankee":
A humorous aphorism attributed to
E.B. White summarizes these distinctions:
To foreigners, a Yankee is an American. To Americans, a Yankee is a Northerner. To Easterners, a Yankee is a New Englander. To New Englanders, a Yankee is a Vermonter. And in Vermont, a Yankee is somebody who eats pie for breakfast.
I only apply to the first three definitions but it speaks true to me.