development area for purposes of this subparagraph. . (b) Effective date The amendment made by this section shall apply to buildings placed in service after the date of the enactment of this Act. 3. HUD study regarding adjustment of tax credit allocations to reflect geographic cost-of-living differences The Secretary of Housing and Urban Development shall conduct a study to identify cost-of-living differences throughout the United States based on geographic location and proximity and accessibility to transit. Not later than the expiration of the 1-year period beginning on the date of the enactment of this Act, the Secretary shall submit a report to the Congress setting forth the results and conclusions of the study and recommending formulas for the adjustment of annual allocations to the States of low-income housing tax credits under section 42 of the Internal Revenue Code of 1986 ( 26 U.S.C. 42 ) to reflect such cost-of-living differences.