How to Take Difference between two table when we are taking counts of other Primary ID

Hi 

My Sceneria is i have a two table Table A and Table B where

Table A has matrix column of Primary Key vs group of City and calulating total count of primary key from Table b

table B has matrix of Column of Primary key vs Group of City from Table A and Calulating Count of Primary key from Table A i want to see the differnece between these two table. I wan to project the difference in Stacked Chart