The issue is that there is 1 question, applying to several shopping centres, to which different number of respondents could have replied. The issue here is to get the denominator for each shopping centre correct, which count(total distinct) is not. It seems as if the following works, where the QD is the dimension of the different shopping centres.
Count(DISTINCT ID)/count(TOTAL <[QD: What Percentage Of All The Money You Spend At Shopping Centres Do You Spend At]> DISTINCT ID)
The next problem is when the question is applying to different product categories in different shopping centres, and you want the graph to display each characteristic for each shopping centre as you then have a question group with 2 dimensions forming the discriminators between the questions in the question group