HFSS: single minimum of dB(S11) over a Frequency Sweep

May someone tell, which function should I use in HFSS to get a single minimum value in dB(S11), whose values are simulated over a given frequency sweep range? Tried 'min' function, but it copies same min. values for entire frequency sweep.

I need this data as a target variable for Optimetrics to optimize. I am not concerned at what frequency is that minima achieved, I just need single min. dB(S11) value in the entire frequency sweep.

Thanks in Advance