(f)
Any statute which authorizes—
(1)
new or liberalized benefits payable from the Fund, including annuity increases other than under section
8340 of this title;
(2)
extension of the coverage of this subchapter to new groups of employees; or
(3)
increases in pay on which benefits are computed;
is deemed to authorize appropriations to the Fund to finance the unfunded liability created by that statute, in 30 equal annual installments with interest computed at the rate used in the then most recent valuation of the Civil Service Retirement System and with the first payment thereof due as of the end of the fiscal year in which each new or liberalized benefit, extension of coverage, or increase in pay is effective.