Thank you for your answer. It somewhat helps, but not fully. It does tell me that earnings are gross but are they gross before both employee and employer social security contributions or net of employer contributions but gross of employee ones? Similarly, does the FICA variable report payroll contributions of both employees and employers or only employees? Hopefully things are consistent, that is if earnings include both types of contributions then FICA also does and if earnings are net of employers contributions then FICA does not include them. But I’m not sure and I haven’t been able to find detailed enough information on this.
Thank you for your help.