You had missed the closing square bracket around the 'Sales' field. See the bracket in bold above. There were additional dimensions in your aggr() function which I'm not sure were needed. You won't need the '=' in your sum([Sales]) expression inside the aggr() if you do put it back in.
Also, I've added the criteria '>= 0.8' because anything on exactly 0.8 will be missing if you just use '<>0.8' between the calculations.