Permissable to use FMedian as a formula in FHist?

I am trying to view (using Showvar) the median EarnYield of a universe for one year ago. In the screener, I tried to create a rule like the following but it failed. I also tried using SetVar but it failed as well. Any ideas on how I can do this? The detailed description for FHist did not say anything about formula restrictions like this.

showvar(@1yragoFMEY,FHist(“FMedian(“EarnYield”)”,52))

I don’t think you can use FMedian inside FHist.

Right.