As with business objects, we recommend that you activate the logging of changes to table data for those tables that are
critical or susceptible to audits. (See the SAP - Audit Guidelines R/3 FI, in Section 4.3.5, for examples of important
tables.) You must also explicitly activate this logging. Note the following:

You must start the SAP System with the rec/client profile parameter set. This parameter specifies whether the SAP System logs changes to table data in all clients or only in specific clients. We recommend setting this parameter to log all clients in your productive system.
In the technical settings (use transaction SE13), set the Log data changes flag for those tables that you want to have logged.
If both of these conditions are met, the database logs table changes in the table DBTABPRT. (Setting the Log data changes flag only does not suffice in recording table changes; you must also set the rec/client parameter.)

You can view these logs using the transaction SCU3.

Although we do deliver pre-defined settings, you generally have to modify them to meet your own requirements. Use the report RSTBHIST to obtain a list of those tables that are currently set to be logged. Use transaction SE13 to change the Log data changes flag for these or other tables.

For more information, also see SAP Notes 1916 and 112388.