§ 637. Computation of separate tax on the ordinary income portion of
lump sum distributions received by nonresident or part-year resident
individuals, estates and trusts. (a) General. The tax imposed under
section six hundred three for any taxable year, with respect to the
ordinary income portion of a lump sum distribution received by a
nonresident or part-year resident individual, estate or trust shall be
applicable to the ordinary income portion of a lump sum distribution
wholly or partly derived from or connected with New York sources, and
the amount of such tax shall be computed in the same manner as that set
forth in section six hundred twenty-four, except that if the lump sum
distribution was partly derived from or connected with New York sources,
the total taxable amount and the ordinary income portion of the lump sum
distribution referred to in such section shall be determined by
apportionment and allocation, pursuant to regulations promulgated by the
state tax commission.

(b) Special rule for part-year residents. In the case of a part-year
resident, the ordinary income portion of a lump sum distribution wholly
or partly derived from or connected with New York sources shall be the
sum of:

(1) The ordinary income portion of a lump sum distribution for the
period of residence, computed as if the taxable year for federal income
tax purposes were limited to the period of residence.

(2) The ordinary income portion of a lump sum distribution for the
period of nonresidence, determined in accordance with subsection (a) of
this section, computed as if the taxable year for federal income tax
purposes were limited to the period of nonresidence.