298 
‘‘(1) a tax is imposed under subsection 
(a)(1) on any unpaid required minimum 
contribution and such amount remains 
unpaid as of the close of the taxable pe-
riod, or 
‘‘(2) a tax is imposed under subsection 
(a)(2) on any accumulated funding defi-
ciency and the accumulated funding defi-
ciency is not corrected within the taxable 
period, 
there is hereby imposed a tax equal to 100 
percent of the unpaid minimum required con-
tribution or accumulated funding deficiency, 
whichever is applicable, to the extent not so 
paid or corrected.’’. 
(2) Section 4971(c) of such Code is 
amended— 
(A) by striking ‘‘the last two sen-
tences of section 412(a)’’ in paragraph 
(1) and inserting ‘‘section 431’’, and 
(B) by adding at the end the fol-
lowing new paragraph: 
‘‘(4) UNPAID
MINIMUM
REQUIRED
CON-
TRIBUTION.—
299 
‘‘(A) IN
GENERAL.—The term ‘un-
paid minimum required contribution’ 
means, with respect to any plan year, 
any minimum required contribution 
under section 430 for the plan year 
which is not paid on or before the 
due date (as determined under sec-
tion 430(j)(1)) for the plan year. 
‘‘(B) ORDERING
RULE.—Any pay-
ment to or under a plan for any plan 
year shall be allocated first to unpaid 
minimum required contributions for 
all preceding plan years in the order 
in which such contributions became 
due and then to the minimum re-
quired contribution under section 430 
for the plan year.’’. 
(3) Section 4971(e)(1) of such Code is 
amended 
by 
striking 
‘‘section 
412(b)(3)(A)’’ 
and 
inserting 
‘‘section 
412(a)(2)’’. 
(4) Section 4971(f)(1) of such Code is 
amended— 
(A) by striking ‘‘section 412(m)(5)’’ 
and inserting ‘‘section 430(j)(4)’’, and
300 
(B) by striking ‘‘section 412(m)’’ 
and inserting ‘‘section 430(j)(3)’’. 
(5) Section 4972(c)(7) of such Code is 
amended by striking ‘‘except to the ex-
tent that such contributions exceed the 
full-funding limitation (as defined in sec-
tion 412(c)(7), determined without regard 
to subparagraph (A)(i)(I) thereof)’’ and in-
serting ‘‘except, in the case of a multiem-
ployer plan, to the extent that such con-
tributions exceed the full-funding limita-
tion (as defined in section 431(c)(6))’’. 
(f) 
REPORTING
REQUIREMENTS.—Section 
6059(b) of such Code is amended— 
(1) 
by 
striking 
‘‘the 
accumulated 
funding deficiency (as defined in section 
412(a))’’ in paragraph (2) and inserting 
‘‘the minimum required contribution de-
termined under section 430, or the accu-
mulated funding deficiency determined 
under section 431,’’, and 
(2) by striking paragraph (3)(B) and 
inserting: 
‘‘(B) the requirements for reason-
able actuarial assumptions under sec-
301 
tion 430(h)(1) or 431(c)(3), whichever 
are applicable, have been complied 
with,’’. 
(g) EFFECTIVE
DATE.—The amendments 
made by this section shall apply to years be-
ginning after December 31, 2006. 
Subtitle C—Other Provisions 
SEC. 121. MODIFICATION OF TRANSITION RULE TO PEN-
SION FUNDING REQUIREMENTS. 
(a) IN GENERAL.—In the case of a plan 
that— 
(1) was not required to pay a variable 
rate premium for the plan year beginning 
in 1996, 
(2) has not, in any plan year begin-
ning after 1995, merged with another 
plan (other than a plan sponsored by an 
employer that was in 1996 within the con-
trolled group of the plan sponsor); and 
(3) is sponsored by a company that is 
engaged primarily in the interurban or 
interstate passenger bus service, 
the rules described in subsection (b) shall 
apply for any plan year beginning after De-
cember 31, 2006.