Well, sadly this won't come as a surprise to many AT&T customers.

The cellular network, whose service coverage has often been lampooned by smartphone users, was just rated last by JD Power and Associates in five of six regions in a new study on network quality and performance.

J.D. looked at network quality in six regions spanning the continental US and in all but one (the Southwest), AT&T ranked either the worst or tied for the worst among the big four. By contrast, Verizon topped the list in five out of six regions, and T-Mobile, whom AT&T is hard at work acquiring, usually ranked in the middle.

Read the whole report here.