§11341

econciliation Act of 1989, Pub. L. 101-239, sec. 7721(b), 103 Stat. 2399, effective for returns the due date for which is after Dec. 31, 1989. Current sec. 6621(c), which was enacted by the Omnibus Budget Reconciliation Act of 1990, Pub. L. 101-508, sec. 11341(a), 104 Stat. 1388-47Ò (effective for purposes of determining interest for periods after Dec. 31, 1990), applies an additional 2-percent interest rate on deficiencies attributable to large corporate underpayments of tax. - 35 - 49 Fed. Reg

(a)(1) 6653(a) 6661 6662 1986 $1,694,871 $423,718 $90,425 -- -- 1987 3,125,107 -- -- $781,277 -- 1988 1,638,186 -- -- 409,547 -- 1989 1,600,390 -- -- -- $320,078 Respondent also determined that Pen Coal's underpayments for the taxable years 1986 through 1989 constitute large corporate underpayments within the meaning of section 6621(c)(3) and that Pen Coal is therefore liable for interest computed at the increased rate prescribed in section 6621(c)(1).2 The notices of 2Sec.