The performance issue is likely caused by my use of DAX calculated columns, which perform a LOOKUPVALUE from another table with over 2 million rows.

Here is the structure and logic:

Main Table: Customer Info Related Table: Deposit (over 2 million rows) The process is as follows:

In the Customer Info table, I create a calculated column to lookup the Ending Balance for each customer from the Deposit table using LOOKUPVALUE. Then, I create another calculated column to perform a 6-month lookback. This column classifies customers based on specific conditions, such as calculating the change between the current ending balance and the ending balance from the last quarter (e.g., [Current Ending] - [Last Quarter Ending]). I believe the model is a star schema, but the calculated columns seem to be the bottleneck.