You could edit the existing Age Debtor report.  In Report Designer, go to Sections and add a new group header, using Sales_Ledger Analysis 1.  Make sure the header appears before the Account_Ref header (move it upwards if necessary).  Then add a data field to the Sales_Ledger.Analysis_1 header.  The data field to use is in the Sales Ledger table, field Analysis 1.

You could edit the existing Age Debtor report.  In Report Designer, go to Sections and add a new group header, using Sales_Ledger Analysis 1.  Make sure the header appears before the Account_Ref header (move it upwards if necessary).  Then add a data field to the Sales_Ledger.Analysis_1 header.  The data field to use is in the Sales Ledger table, field Analysis 1.