Filled Map Drilldown and Pie Chart Filtering - Need Help

I'm using the filled map visual and pie chart visual. For the filled map in the location field I'm using states/provinces at the top of hierarchy then cities below and a gradient based on total sales. For the pie chart I'm using the same data - states/provinces and cities in the legend and sales in the value.

The default view is: 

When I drill down via the map however (say I drilldown on Michigan because I want to view the cities) the map will drill down displaying the cities however the pie chart just shows the total sales for that state - it doesn't show a breakdown of the cities by sales. This is the view:

How do I get the pie to automatically show me the sales data by city rather than the total of the state when I click on the state on the map?

Thank you.