Numerous reports have stated that the only reason Undertaker has been featured on Raw and Smackdown since Wrestlemania is because CM Punk is out of action, The Rock has left and Brock Lesnar only has a limited amount of dates he can appear. Those are some of WWE's biggest draws and without them or the Undertaker, ratings would most likely drop.
Of course Taker staying is fully up to him and how he feels and from this past Monday's six man tag on Raw where he teamed with Kane and Daniel Bryan to take on the Shield, Taker seems to be in pretty good shape considering the reasons why he only wrestles once a year.
I doubt Undertaker will stay the full year. I wouldn't be surprised if we see Taker leave WWE before the summer. However, until CM Punk returns (which is said to be late May) Undertaker will continue to wrestle.
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