Section 620-A. Credit against separate tax

(a) General. A resident shall
  be allowed a credit against the separate tax otherwise due under section
  six hundred three for any income tax imposed for  the  taxable  year  by
  another  state  of  the  United  States, a political subdivision of such
  state or by the District of Columbia, upon the ordinary  income  portion
  (or  part thereof) of a lump sum distribution both derived therefrom and
  subject to tax under such section.  Where such ordinary  income  portion
  (or  part thereof) of a lump sum distribution is not subject to separate
  income taxation by such other state or its political subdivision  or  by
  the  District of Columbia, but is included as income under an income tax
  imposed by such jurisdiction, the portion of  the  tax  on  such  income
  which constitutes the income tax imposed on such ordinary income portion
  (or  part thereof) of a lump sum distribution shall be an amount bearing
  the same ratio to the entire tax paid to such other jurisdiction as  the
  amount  of  the  ordinary income portion (or part thereof) of a lump sum
  distribution included in the income subject to such  tax  bears  to  all
  income subject to such tax.
    **  (a)  General.  A  resident  shall  be allowed a credit against the
  separate tax otherwise due under  section  six  hundred  three  for  any
  income  tax  imposed for the taxable year by another state of the United
  States, a political subdivision of such state, the District of  Columbia
  or  a  province  of  Canada,  upon  the ordinary income portion (or part
  thereof) of a lump sum distribution both derived therefrom  and  subject
  to  tax under such section.  Where such ordinary income portion (or part
  thereof) of a lump sum distribution is not subject  to  separate  income
  taxation  by  such  other  state  or  its  political  subdivision or the
  District of Columbia or a province of Canada, but is included as  income
  under an income tax imposed by such jurisdiction, the portion of the tax
  on such income which constitutes the income tax imposed on such ordinary
  income  portion (or part thereof) of a lump sum distribution shall be an
  amount bearing the same ratio to the  entire  tax  paid  to  such  other
  jurisdiction  as  the  amount  of  the  ordinary income portion (or part
  thereof) of a lump sum distribution included in the  income  subject  to
  such tax bears to all income subject to such tax.
    ** NB Applies to taxable years commencing after December 31, 1987
    (b)  Limitations.  (1)  The credit under this section shall not exceed
  the percentage of the tax otherwise due under section six hundred  three
  determined  by  dividing  the  portion of the taxpayer's ordinary income
  portion of a lump  sum  distribution  taxable  both  under  section  six
  hundred  three and by such other jurisdiction by the total amount of the
  taxpayer's ordinary income portion of a lump  sum  distribution  taxable
  under section six hundred three.
    (2)  The  credit under this section shall not reduce the tax otherwise
  due under section six hundred three to an amount less  than  would  have
  been  due  if  the  portion of the ordinary income portion of a lump sum
  distribution taxable both under section six hundred three  and  by  such
  other  jurisdiction  were  excluded from the computation of the separate
  tax imposed under section six hundred three.
    ** (3) In the case of a taxpayer who elects to claim the  foreign  tax
  credit  for  federal  income tax purposes, the credit under this section
  for income tax imposed by a province of Canada shall be allowed for that
  portion of the provincial tax not claimed for federal purposes  for  the
  taxable  year  or  a  preceding  taxable  year, provided however, to the
  extent the  provincial  tax  is  claimed  for  federal  purposes  for  a
  succeeding  taxable  year,  the  credit under this section must be added
  back in such succeeding taxable year. The provincial tax shall be deemed
  to be claimed last for federal income tax purposes and for  purposes  of
  this subsection.

    * NB Applicable to taxable years beginning after 1986.
    ** NB Applies to taxable years commencing after December 31, 1987