Waterfall Forensics.

Prime hybrid ARM RMBS (two pools: shifting-interest and overcollateralization)

Citigroup Mortgage Loan Trust 2006-AR6

424B5 filed 2006-08-31, acc 0000882377-06-002994

machine-encoded from the prospectus by the extraction pipeline and tied out over 4 periods (2006-09-25 to 2006-12-26); not yet expert-verified

Backtested periods

4

2006-09-25 to 2006-12-26

Comparison points within $1

82.9%

216 points

Max principal delta

$0.01

interest $1156233.06 · balance $0.02

What the encoder found in the filings

  • group 1 has 3 senior classes (1-A1, 1-A2, 1-R); assumed pro rata, but the contract may pay them as components — check the tie-out
  • group 2 has 4 senior classes (2-A1, 2-A2, 2-A3, 2-A4); assumed pro rata, but the contract may pay them as components — check the tie-out
  • subordinate stack per loan group: encoded as group 1 (3 senior + 6 subordinate), group 2 (4 senior + 5 subordinate) and tied out separately; cross-collateralization after a group's seniors retire is not modelled
  • group 1: window starts at deal month 1 (2006-09-25); earlier reports are not in the machine-readable run
  • group 2: window starts at deal month 1 (2006-09-25); earlier reports are not in the machine-readable run

Capital structure · original faces

1-A1
$700,817,000.00
1-A2
$39,106,000.00
1-R
$100.00
2-A1
$345,707,000.00
2-A2
$110,154,000.00
2-A3
$134,526,000.00
2-A4
$65,598,000.00
1-B1
$18,198,000.00
1-B2
$5,808,000.00
1-B3
$3,872,000.00
1-B4
$2,322,576.00
1-B5
$2,322,576.00
1-B6
$1,936,628.00
2-M1
$16,042,000.00
2-M2
$10,811,000.00
2-M3
$4,534,000.00
2-M4
$3,487,000.00
2-CE
$6,626,495.00

viridian = senior (per-pool) · burgundy = cross-collateralized subordinates

Worst remaining deltas · computed vs reported

interest

2006-09-252-CE-1156233.06
2006-12-262-CE-702092.00
2006-10-252-CE-628408.67
2006-11-272-CE-315166.16
2006-09-252-A1+257788.98

principal

2006-10-251-B6-0.01
2006-09-251-B6+0.01
2006-10-251-A1+0.01
2006-11-271-A1+0.01
2006-09-252-A1+0.01

ending balance

2006-11-271-A1-0.02
2006-12-261-A1-0.01
2006-10-251-A1-0.01
2006-09-251-B6-0.01
2006-12-261-B3+0.01