Carry Forward Previous Week’s Snapshot for Current Week in Tableau (Without Affecting Future Weeks)

Dear Community Members,

I have a requirement where, in a quarter, the snapshot value from the previous week should populate for the current week. However, the values for all future weeks should remain unchanged. How can I achieve this in Tableau?

Find the example below:

The total finally should be:

I have also attached a workbook with test data.

Your help is appreciated. Thank you in advance.

Best regards,

Avinash P Rao