Ratings from banks typically don't have an time horizon beyond a year. In the following video, Motley Fool analyst Taylor Muckerman dissects changes for three midstream companies. For him, the two upgrades should hold for longer than a year given the market prospects for natural gas liquids. ONEOK Partners (NYSE:OKS) is even a company that he has been following for quite some time. Why might this company and a peer have been upgraded while a somewhat similar midstream company lost a spot on the ratings ladder? Tune in below for our take.

Joel South has no position in any stocks mentioned. Taylor Muckerman has no position in any stocks mentioned. The Motley Fool recommends ONEOK Partners, L.P.. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.