SUM of Row Count by Column Value

I've been trying to understand the DAX code required to build a calculated column that addresses count based on conditional formatting.

I have two tables, one table is acting as a summary table for FICO data for further analysis. The other table is the source table for the data.

I have a range value (FICO Band) for all rows in the source table. I would like to count (for total) the occurrences of each of one these values and import this count into the summary table via a calculated column named something like Count of FICO Range.

Entries in Source TableSummary Table

Any assistance in crafting the DAX for the calculated column would be appreciated.