Your requirement is to add Statistical Time Account in the Employee Time Statement.
Reproducing the Issue
1. Go to Time Administration workcenter.
2. Select Timesheet view
3. Search Employee ID.
4. Select Time Statement button.
The Statistical Time Account data is missing from Time Statement for the employee.
The Employee Time Statement shows only Quota and Working Time Account details.
You cannot find any Statistical Account in this report.
There is no documentation for the Time Account addition process, this gets populated by default as per standard settings.
Statistical Time Account, Employee Time Statement , KBA , SRD-HR-TLM , Time and Labour Management , How To