(a) Every employe of the Commonwealth, whose services are covered by an agreement entered into under section four,¹ shall be required to pay for the period of such coverage, into the Contribution Fund established by section seven,² or other restricted receipt account established for such purpose, contributions, with respect to wages (as defined in section two of this act³ ), not in excess of the amounts prescribed under the provisions of the Federal Insurance Contribution Act.⁴ The actual amount of the contributions to be made under the provisions of this paragraph shall be the amount necessary to carry out the provisions of this act and the agreement entered into in accordance therewith, which amounts shall, from time to time, be determined by the State Agency, subject to the limitations herein prescribed; each liability shall arise in consideration of the employes retention in the service of the Commonwealth, or his entry upon such service after the enactment of this act.

(b) The head of each department shall cause to be deducted on each and every pay-roll of an employe, for each and every pay-roll period subsequent to the effective date of an agreement entered into under this act, such percentum of the total amount of wages earnable by the employe in such pay-roll period required to satisfy the contribution imposed by clause (a) of this section, and shall certify to the Treasurer of the Commonwealth on account of each and every pay-roll of an employe a statement as voucher for the amounts to be deducted, but failure to make such deductions shall not relieve the employe from the liability for such contribution.

(b.1) The State Treasurer, on receipt from the heads of the departments of the vouchers for deductions from the wages of employes provided for in clause (b) of this section, shall make such deductions and shall pay each of the amounts so deducted into the contribution fund established by section 7 of this act or such restricted receipt account as may be established for this purpose.

(b.2) The Treasurer or paying officer, on receipt from the heads of the departments of the vouchers for deductions from the wages of employes provided for in clause (b) of this section, shall make such deductions and shall pay each of the amounts so deducted into the contribution fund established by section 7 of this act or such restricted receipt account as may be established for this purpose.

(c) If more or less than the correct amount of the contribution imposed by this section is paid or deducted with respect to any remuneration, proper adjustments or refund, if adjustment is impracticable, shall be made without interest in such manner and at such times as the State Agency shall prescribe.