Please see the below table:

The first column is the account, the second column is the sub-account, the third column is the description for the combined account with the sub-account.
I need to change the information in the fourth column to show the description located in the '00' sub account for each account For example, in the column labeled "'00' Description", I need to show all sub-accounts of 900654 with the description 'Space Rental'.
I need to show all sub-accounts of 900760 with the description 'Administrative Overhead', etc. .
Thanks in advance for your help.
Bob