Variables

[MahaMohamed]

I have a table box on qlikview showing the ordered quantities per each city on daily basis, i need to add expresion to calculate the variance between the quantity of the capital city vs the other cities in each day as below 

 

I created a variable = sum ({<City={"City1 (Capital) "} >} Quantity)

And i added an expresion with the variable and another one to calculate the variance, but the variable value shows the total quantity of the capital city for all the days not per each day as below

 any help please ?