Number (currency) formatting on formula column

Hello, I have a board set up for marketing campaign management and planning. In this board, I have a parent item for a campaign and use subitems for each initiative in the campaign. Each subtask/marketing initiative has a cost, count of of leads generated and a formula column that calculates the cost per lead (CPL). I added a summary of the CPL column on the parent item and changed “Show summary as” to “Average”. It works great, but since this is a financial column, I need to change the number format to currency. I know there is functionality to change regular column numbers to currency, but don’t see that function on a formula field. Am I missing it somewhere? If not, could this functionality be created? Thanks in advance!