Section 23. Employers' contributions and their use; pension accumulation fund

a. Except as otherwise provided pursuant  to  this  article,  the
  pension   accumulation  fund  shall  be  the  fund  in  which  shall  be
  accumulated:
    1. All contributions made by employers, and
    2. All income received from the investments of the retirement  system,
  and
    3.  All  monies  received  from  all  other  sources and which are not
  required to be credited to any other fund.
    b. Each employer shall make two contributions annually. They shall  be
  known  as  the  normal  contribution  as  defined in subparagraph (a) of
  paragraph one of this subdivision and  the  deficiency  contribution  as
  defined in paragraph two of this subdivision. The rates thereof shall be
  computed by the actuary.
    1.  (a)  Normal  contribution.  The rate of such contribution shall be
  applied to the members' annual compensation as of the end of the  fiscal
  year.  Such  rate  shall  be  a  uniform and constant rate per centum of
  annual compensation when determined by dividing the valuation  costs  by
  the  payroll amount used in the valuation. Notwithstanding any provision
  of law to the contrary, the valuation costs consist of:
    (i) the normal cost, which shall be the actuarial present value of the
  employer provided benefits accrued  during  the  year,  based  upon  the
  projected  future  salary  on which benefits are expected to be paid, by
  prorating each employee's projected benefit over his or her total  years
  of service;
    (ii)  the  supplemental  cost,  which  shall  be the cost of providing
  supplemental retirement allowance payments pursuant to subdivision e  of
  section seventy-eight of this article;
    (iii)  the  administrative  cost,  which  shall be the expenses of the
  retirement system pursuant to paragraph three of subdivision b  of  this
  section;
    (iv)  the  prior service cost, which shall be equal to the interest on
  the unfunded actuarial accrued liability or surplus plus  a  portion  of
  the  unfunded  liability  or  surplus,  said  portion to be equal to the
  unfunded liability or surplus divided by the  average  future  years  of
  service of active employees; and
    (v)  the  annual amortization cost, which shall be equal to the amount
  of the annual amortization payment required to be paid into the system's
  pension accumulation fund under sections sixteen-a  and  seventeen-a  of
  this article.
    Provided,  however,  in  no  event shall the amount of contribution be
  less than zero.
    (b) The comptroller is authorized to make appropriate adjustments  for
  those  participating employers that have paid an amount in excess of the
  minimum annual amortization payment required by section  seventeen-a  of
  this  article.  The excess payment shall accumulate with interest earned
  at the rate used in  the  annual  actuarial  valuation  and  be  applied
  against  future  pension  contribution  requirements to insure equitable
  treatment of all participating employers.
    (c) In any year in which no contribution is required  to  the  pension
  accumulation  fund,  any adjustment reducing a prior year's contribution
  resulting from the enactment of section sixteen-b of this chapter, shall
  be credited with  interest  earned  at  the  rate  used  in  the  annual
  actuarial valuation and applied against future pension contributions.
    Such  rate  shall  be  computed  each  year  by  means of an actuarial
  valuation as prescribed in section eleven of this chapter.
    2. Deficiency contribution.

    (a) In the case of employers participating  on  July  first,  nineteen
  hundred  forty-eight, the rate of such contribution shall continue to be
  the rate theretofore determined  pursuant  to  law.  Such  rate  may  be
  varied,  however,  if  an  adjustment  is  necessitated by reason of the
  allowance of additional prior service credits.
    (b)  In  the  case  of  an employer electing to participate after July
  first, nineteen  hundred  forty-eight  and  before  March  thirty-first,
  nineteen  hundred  ninety-nine,  an initial actuarial valuation shall be
  made to determine the accrued liability of such employer by  reasons  of
  the  prior  service  of  those  of  its employees who are members of the
  retirement system. The rate of deficiency contribution for such employer
  shall then be determined. Such rate shall  be  that  proportion  of  the
  total annual compensation of such employees as is equivalent to four per
  centum  of  such  accrued  liability.  Such rate shall be applied to the
  employer's payroll of members, as used in the annual valuation. The cost
  of making such initial valuation shall be assessed against and  paid  by
  such employer.
    Notwithstanding the above, for employers who commence participation in
  the  retirement  system  on  or  after  April  first,  nineteen  hundred
  ninety-nine, the accrued liability shall be amortized  in  equal  annual
  installments  over  a  twenty-five  year  period.  With  respect to such
  employers the cost of making such initial valuation  shall  be  assessed
  against  and  paid  by the employer. The provisions of subdivisions c, d
  and e of  this  section  shall  not  apply  to  employers  who  commence
  participation in the retirement system on or after April first, nineteen
  hundred ninety-nine.
    (c) The amount of each annual deficiency contribution payable by every
  employer  shall be at least three per centum greater than the amount for
  the preceding year.
    (d) The comptroller shall approve the discontinuance  of  the  state's
  deficiency contribution on account of members employed by it when:
    (1)  The  total  amount in the pension accumulation fund on account of
  all members, and
    (2) The present value of future deficiency contributions still  to  be
  paid by other employers, and
    (3)  The present value of future normal contributions, on the basis of
  the rate of normal contribution then in effect,  shall  equal  the  then
  present  value  of  the total liability of such fund on the basis of the
  tables then in use.
    (e) Unless previously discontinued, or unless  hereafter  discontinued
  pursuant  to  other  provisions of law, the deficiency contribution of a
  participating employer shall be discontinued when the  total  amount  of
  deficiency  contributions paid by such employer at least equals or shall
  hereafter equal such percentum of its initial accrued liability computed
  by the actuary as shall equal that  percentum  of  the  state's  initial
  accrued  liability  paid  by  deficiency contributions during the period
  equal to the period last determined by the  actuary  as  the  deficiency
  payment  period.  Nothing  herein  contained shall be deemed to give any
  participating employer any valid claim or cause of action for refund  or
  credit  for any sum or sums paid or to be paid for fiscal years prior to
  and including  the  fiscal  year  ending  March  thirty-first,  nineteen
  hundred  sixty-six  nor  to  excuse  any participating employer from the
  payment of any contributions for such fiscal years.
    3. Administration contribution.
    (a) The  expenses  of  the  retirement  system,  including  an  amount
  allocated  to amortize over a period of thirty years, with interest, the
  cost of construction of the retirement system building, and the cost  of
  maintenance  of  such building, for each fiscal year shall be determined

  at the close of each such year. The ratio of such expenses to the  total
  compensation  of  all members, as used in the actuarial valuation, shall
  be the rate of such administration contribution.   Such  rate  shall  be
  applied  to  each  employer's  payroll of members, as used in the annual
  valuation.
    (b) All such expenses shall be paid out of  the  pension  accumulation
  fund  which shall be reimbursed through administration contributions and
  other monies received from employers pursuant to this article.
    (c) Notwithstanding any other provision of  this  subdivision  or  any
  other  law,  the  administrative  contribution for a year, as determined
  pursuant to paragraph one of subdivision b of  this  section,  shall  be
  paid  from  the pension accumulation fund if payment from such fund will
  not affect the normal contribution for such year.
    c. Additional contributions shall be made in accordance  therewith  by
  employers  obligated  to contribute to the retirement system pursuant to
  any other section of this article.
    d. When a pension or a  pension-providing-for-increased-take-home-pay,
  if any, becomes payable to or on account of any member, a reserve, in an
  amount computed by the actuary to be necessary to provide the pension or
  pension-providing-for-increased-take-home-pay,  if  any, granted in each
  such case, shall be transferred from the pension  accumulation  fund  to
  the pension reserve fund.
    e. Whenever the comptroller, upon recommendation by the actuary, shall
  determine  that  it  is  necessary  to increase the reserves held in the
  annuity reserve fund or the pension reserve fund, he may direct that the
  amount  so  needed  shall  be  transferred  thereto  from  the   pension
  accumulation fund.
    f.  The  amount  of  regular  interest  which is to be credited to the
  annuity savings fund, the annuity reserve fund and the  pension  reserve
  fund,  and  the  amount  of  special  interest,  if  any, which shall be
  credited to the annuity savings accounts in the  annuity  savings  fund,
  shall  be  determined  after  the  close  of each fiscal year. Each such
  amount thereupon shall be transferred from the pension accumulation fund
  to each such fund.