Forecast of a race duration during the race itself

Hi all, is it possible to have the "total time forecast" during a run?

Example, I set a half marathon as workout and would like to have a constant forecast of what will be my total time depending the actual pace.

I tryed on different fields but I did not find the right one. I found "forecasted time to the end" but not the "forecasted total time to cover the distance" 

Thanks!