Background: New York Corporation which is domiciled in New York. Income consists exclusively of interest from bank CDs and interest from US Treasuries.
Interest from US Treasuries is exempt from New York income tax.
Question: Where on New York corporate tax return (Form CT-3) do I list interest from US treasuries to subtract from federal taxable income? Form CT-225 does not seem to work because provisions applicable to US Treasury interest are limited to S-Corps. Form CT-3.1 has line for inserting "Gross investment income from investments generating income not taxable by New York under the U.S. Constitution," but instructions indicate that this can "only be claimed by entities domiciled outside New York State" (which is not the case for my situation).
Any help would be greatly appreciated.