How to define the carry forward of retained earnings account

see as referenced in the help.sap.com documentation

https://help.sap.com/viewer/0fa84c9d9c634132b7c4abb9ffdd8f06/LATEST/en-US/49c2d553088f4308e10000000a174cb4.html

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Profit and loss accounts Profit and loss accounts are carried forward to one or more retained earnings accounts.

When balance carryforward is performed, the balance of the profit and loss account is set to zero.

see also reference: Balance Carryforward Details

You can use the following apps to view balance carryforward details:

In the Balance Carryforward Status app, you can view details about the balance carryforward, such as the status, when it was run, and more.

In the Journal Entry Analyzer app, you can display the balance that was carried forward from the previous fiscal year. You can also compare the ending balance of one fiscal year with the starting balance of the next fiscal year.

For more information, see View Details in the Journal Entry Analyzer App https://help.sap.com/viewer/0fa84c9d9c634132b7c4abb9ffdd8f06/LATEST/en-US/b2bc42c5c25f46ff854371fd58ae2690.html

If you want to compare the starting balance of the retained earnings account to the ending balance of profit and loss (P&L) and retained earnings accounts for the previous fiscal year, you must also: Specify the P&L account in the G/L Account field and select GO to view the ending balance for the previous fiscal year. (The starting balance is always zero.)

Specify the retained earnings account in the G/L Account field and select GO to view the starting balance for the current fiscal year.

To view the breakdown of starting balances in the retained earnings account, open the Navigation Panel and under Available Fields add Offsetting Account to the rows axis.

The starting balance of the retained earnings account is broken down between the corresponding P&L accounts (and retained earnings account).

You can use this information to compare the breakdown of starting balances in the retained earnings account to the ending balance of P&L accounts (and retained earnings accounts).

see also note https://launchpad.support.sap.com/#/notes/2969938 which shows where ◦Define Retained Earnings Accounts (transaction key BIL) is maintained