Formatting a matrix column grouping

Hello,

I have a SSRS 2010 Matrix table that I'm trying to format properly.  I have a column group field named BUYS_SELLS that is summing up my PROCEEDS field into 'AUM', 'AUM PERCENTAGES', 'BUYS', 'SELLS', 'NEW_MONEY' buckets.  This seems to be working properly but I'm running into issues with formatting.

I would like 'AUM', 'BUYS', 'SELLS', 'NEW_MONEY' to be formatted as currency and 'AUM PERCENTAGES' to be formatted as a percent.

Using the textbox properties is not letting me control the 'AUM PERCENTAGE' format on its own.  Is there any way to control the formatted with logic with a expression?

Any help would be greatly appreciated.

Thanks,

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