Many thanks for your answer!
Unfortunately, I could not managed to make it work. I tried with Export=no in the equation, but then the value of the Id is not visible in the table (I am trying to print the values in the table). When I write the equations average(Id) in the table I get one value also. i guess the problem is in range function as I see Id as a single vector. But anyway, it is important that you know that there is a bug.