For the United States, the agreement applies to Social Security taxes under the retirement,
            survivors and disability insurance (RSDHI) program (i.e., FICA taxes for employment
            and SECA taxes for self-employment, including the Medicare portion). Thus, if an individual
            is exempt from U.S. Social Security coverage under this agreement, neither the employee
            or employer share of the FICA tax nor the SECA tax, in the case of a self-employed
            person, has to be paid.