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Methodology or Forecasting andStress-Testing ABS and RMBS Deals
August 5, 2010
Prepared By
ECONOMIC & CONSUMER CREDIT ANALYTICS
Juan Carlos CalcagnoSenior [email protected]
Anthony HughesSenior [email protected]
Ioannis StamatopoulosAssistant [email protected]
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Methodology or Forecasting andStress-Testing ABS and RMBS Deals
The nancial crisis has demonstrated the urgency o developing new tools to improve nancial
decision-making. The need or research and development is especially great in the structured
securities market, which was at the epicenter o the crisis. Structured nance originations have
now virtually dried up, to the detriment o not only investors, but also consumers. I investors can ac-
curately value and assess the risks o their holdings, bonds can be priced correctly, and the benets
o securitization can then fow to them as well as to consumers in the orm o lower interest rates on
mortgages, auto loans, student loans and credit cards.
In general, structured nance deals are put together by pooling groups o consumer loans and plac-
ing the principal and interest paid by borrowers into a kitty to be distributed to investors who ownthe rights to dierent tranches representing dierent degrees o risk. A deal is oten composed o
numerous pools o loans, each with distinct characteristics. Complex rules govern how the money in
the kitty is distributed to investors. Some investors may be more exposed to a particular pool within
a deal than others who hold bonds carrying the same rating. Conversely, the pools may all pay into a
common kitty, in which case the division into pools serves a purely administrative unction. The value
o the bonds is thus determined by the extent to which the loan pools are able to contribute cash to
the kitty. The accuracy o orecasts o these cash streams should thereore be the objective o any
model used to assess bond value.
In this paper, we outline the approach Moodys Analytics uses to model, orecast and stress-test
collateral backing ABS deals, concentrating on U.S. RMBS. Since the Moodys Analytics Structured
Finance Workstation already precisely handles the waterall modeling problem, our task here is to
develop a methodology that accurately projects the cash fow rom the collateral backing the deals.
Our approach considers economic conditions at loan origination, loan characteristics, past pool per-
ormance, and dynamics in the macroeconomic environment over time to explain changes in pool
perormance. We will describe, in detail, our methodology, and the models developed will be vali-
dated against simple and similar alternative orecasting approaches. The same methodology has been
successully applied to other types o asset-backed securities such as international RMBS, auto ABS,
student loans, credit cards, and business leases. In all cases, the methodology is immediately andglobally available, allowing any type o security, provided data are available, to be accurately valued
and stress-tested. The output rom the models described in this paper provides all necessary data to
run waterall valuation engines and thus compute air value and expected loss under baseline as well
as stressed conditions.
MOODYS ANALYTICS / METHODOLOGY FOR FORECASTING AND STRESS-TESTING ABS AND RMBS DEALS
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MOODYS ANALYTICS / METHODOLOGY FOR FORECASTING AND STRESS-TESTING ABS AND RMBS DEALS 2
The MoodysAnalytics Approach
We eel that a pool-level approach is like-
ly to provide greater utility to end users than
competing methodologies. Data at this level
are available on securities rom all parts o
the world and on any product, meaning that
the pool-level approach is universally appli-
cable. Pool-level models are also more likely
to provide accurate orecasts o pool-level
aggregates than are competing approaches.
The data used or this study are drawn
primarily rom two sources: The Moodys
Analytics U.S. macroeconomic orecast
databases and the Moodys Analytics Peror-
mance Data Services product.
Moodys Analytics maintains one o thelargest repositories o macroeconomic,
demographic and nancial data rom a mul-
titude o government and private sources.
The data set covers the national accounts,
banking and nance, demographics, personal
income, prices, retail sales, labor markets,
energy, nancial markets and many other
indicators. Moodys Analytics each month
produces projections, both baseline and
stressed, or economies and nancial mar-
kets worldwide using large-scale structural
macroeconometric models. In the broadestterms, the models are specied to refect the
interaction between aggregate demand and
aggregate supply. In the short run, fuctua-
tions in economic activity are primarily de-
termined by shits in aggregate demand, in-
cluding personal consumption, gross private
investment, net exports, and government
expenditures. The level o resources and
technology available or production is, in the
short term, taken as givens. Prices and wages
then adjust slowly to equate aggregate de-
mand and supply and thus move the econo-my toward equilibrium. In the longer term,
changes in aggregate supply determine the
growth potential o the economy. The rate
o expansion o the resource and technology
base is the principal determinant o overall
economic growth, which eeds, interactively,
into other actors in the model. The model
and subsequent orecast are overseen by a
team o about 60 economists who cover the
perormance o the economy in real time.
The orecasts undergo continual revision
and adjustment to refect new trends and
changing data. Recent advances in macroeco-
nomic theory, new econometric techniques,
and increased computing power also govern
development o the models. The system has
been changing to accommodate increased de-
mand by clients who want to use the models
to generate alternative scenarios and to un-
derstand the sensitivity o the macroeconomy
to changing economic and nancial condi-
tions. Moodys Analytics produces one upside
and several downside alternative scenarios
each month or each economy it covers. A de-
tailed description o some recent alternative
scenarios is included in Appendix 2.
In terms o the ABS credit data, mean-
while, PDS is a comprehensive and standard-ized data set that includes raw inormation
on all active and inactive ABS and RMBS
deals rated by Moodys Investors Service in
the U.S. and globally. For a more compre-
hensive picture o the U.S. RMBS market
during the model development stage, and
to avoid any selection bias, we have supple-
mented the PDS data set with inormation
rom deals that are not rated by MIS; this
supplemental database is available only in-
ternally. Given that MIS-rated deals cover
about 90% o the U.S. RMBS universe, thePDS product alone is close to comprehen-
sive, given the aims o this paper.
The data set is composed o deal inorma-
tion at origination, augmented by continu-
ously updated perormance inormation
rom servicer and trustee monitoring reports.
The data les are cleaned and validated
by the MIS monitoring team as part o the
ongoing ratings surveillance process. The
data are o excellent quality and o a perect
structure or the orecasting models con-
sidered in this article. Included in the lesare over 100 perormance statistics at the
deal, pool, and tranche level or over 10,000
ABS and RMBS deals in the U.S., Europe, the
Middle East and Arica as well as in the Asia-
Pacic region. PDS coverage in each region
matches the market share o MIS in rating
the underlying deals. The data are not only
consistent within each region or country,
they are also consistent across and between
regions, allowing or international analysis
i so desired. Our analysis typically con-
centrates on key pool perormance metrics
such as delinquency rates as a proportion o
original balance, longer-term indicators o
deault, prepayment rates, and severity o
losses or loss given deault.
For the purposes o this study, because
o the lack o data on a ew key variables,
we restrict our attention to U.S. RMBS deals
originated ater December 2001. Many
perormance measures, however, are avail-
able back to 1995. Table 1 provides basic
descriptive statistics about the pools in the
sample used or modeling purposes. The
pools employed are concentrated in sub-
prime, alt-A and jumbo categories. Given
that originations grew so quickly rom 2004
to 2007, unsurprisingly, these cohorts arealso very well represented. Data or other
vintages and product types are suciently
available or their determining actors to be
accurately estimated.
Once all data les are merged, the nal
data set used or the analysis is a multi-
dimensional, longitudinal panel data set.
Our estimation sample is composed o
12,148 unique asset pools observed over, in
most cases, several years. In total, our es-
timation sample or most dependent vari-
ables amounts to about 660,000 uniqueobservations with a ew categories, most
notably loss severities, having access to
only about 140,000 separate observations.
The data cover a ull business cycle, includ-
ing two recessions, allowing us to correctly
measure the impact o cyclical actors and
to weigh these actors against internal
pool-specic inormation.
A. The econometric model
The panel nature o the data on struc-
tured securities provides a rich tapestry withwhich to construct high-quality orecasting
models. In this paper, we consider a model
o the orm
or, decomposing into its constituent
components:
ECONOMIC & CONSUMER CREDIT ANALYTICS
(1)
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MOODYS ANALYTICS / METHODOLOGY FOR FORECASTING AND STRESS-TESTING ABS AND RMBS DEALS 5
ECONOMIC & CONSUMER CREDIT ANALYTICS
healthy dose o economic principle. Models
built this way enjoy the additional benet o
ease o interpretation.
The selection o the explanatory macro-
economic variables was also based on our
ability to orecast them easily and suciently
accurately. In econometric orecasting, the
uture realizations o the dependent variablerely on accurate orecasts or the independent
variables. Forecast errors can easily be multi-
plied i input variable orecasts are not closely
monitored or i the data backing the orecasts
are noisy and thus inherently dicult to
project. Identiying macro variables that are
useul in this context is straightorward: They
are the actors that oten have the power to
change the direction o nancial markets and
that are thus routinely debated in the public
square. Variables such as unemployment
rates, home price indices, key interest rates,and retail sales numbers are generally bet-
ter candidates than industry-level mortgage
oreclosure rates, or instance, which are o
interest only during certain brie periods. We
nd that a combination o such core variables
generally act as a reasonable proxy or these
more peripheral actors. Since core variables
are generally easier to predict, we nd them
more useul in building optimal orecasts o
ABS pool perormance.
Model Results
A summary o the variables included in
each regression or the vectors we modeled
is presented in Table 2. The rst group o vari-
ables, the pool origination actors ( in (2)),
include average LTV and FICO, a set o dum-
mies or vintage origination year, dummiesdening loan or collateral type (i.e. whether
the pool represents subprime or jumbo
mortgages, or instance) and a set o dum-
mies indicating whether the originator o the
pool in question was in the top 10 in terms o
total number o pools originated during the
in-sample period. The vintage year, collateral
type and originator dummies are included
in most regressions in order to control or
group heterogeneity in the data. Weighted
average LTV and FICO at origination are
key pieces o inormation not only becausethey determine pool quality and hence
perormance, but also because we seek to
retain the ability o the models to project the
perormance o newly originated mortgage
pools using inormation that is readily avail-
able at deal origination.
The second group o variables includes
the economic condition actors at deal origi-
nation, which is our set o instrumental vari-
ables, . In this category, we ound that gen-
eral measures o economic activity, like GDP
and the unemployment rate, are correlated
with changes in pool perormance; we also
nd good support or actors specic to the
mortgage market such as home prices and
interest rates. Broadly speaking, house price
changes and an average benchmark interest
rate at origination tend to have a counter-cyclical impact on measures o perormance
observed early in the deault process. Labor
market conditions at deal origination, how-
ever, become more important when model-
ing later stages in the deault process, includ
ing oreclosure, REO, and losses.
The third set o variables is the macro-
economic series or those actors related to
the pools exposure to the business cycle.
We ound that the types o macroeconomic
actors that aect delinquency are standard
are labor and housing market variables,income, and overall economic activity with
close attention paid to lag structures and
transormations applied to the economic
data being used. House price changes and
renancings become much more important
drivers at later stages in the oreclosure pro-
cess. We use both current home price chang-
es and price changes since origination as key
housing market actors. This second variable
allows or a dierential negative equity e-
TABLE 1
Number o pools by collateral type and closing year
Pools Collateral Type
Deal Closing Year
Total2002 2003 2004 2005 2006 2007 2008 2009 2010
HELOC 14 23 61 50 46 20 2 216High LTV 14 10 6 7 6 1 44
Home Equity/Closed End 2nds 8 8 6 6 19 14 61
Subprime 287 526 749 795 777 386 4 3,524
Alt-A 155 463 1,080 1,335 904 676 12 1 4,626
FHA-VA 9 17 17 25 20 2 90
Jumbo 207 583 534 452 315 252 30 2 1 2,376
Prime Conorming 5 1 6
Scratch & Dent 10 25 63 43 49 41 231
Subprime 2nds 2 13 27 51 83 41 217
Option Arms 5 71 221 284 173 3 757Total Pools 706 1,673 2,619 2,985 2,503 1,606 51 3 2 12,148
Average Time-Series Available 92 82 70 58 46 36 23 10 2
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MOODYS ANALYTICS / METHODOLOGY FOR FORECASTING AND STRESS-TESTING ABS AND RMBS DEALS 6
ECONOMIC & CONSUMER CREDIT ANALYTICS
ect to be explicitly modeled. The models o
oreclosure, REO, charge-os, and severity
are tied largely to home prices and various
other actors aecting housing and legal cost
structures. We also ound prepayment rates
to be more sensitive to interest rates, re-
nancing activity, and existing-home sales.
As the structure o the model is recursive
in nature, the next set o covariates consti-
tutes the so-called pipeline connections. We
model delinquencies largely independently
o one another but model subsequent events
prepayments, oreclosures, charge-os, and
severity conditionally on the delinquency
perormance the pools attain. We also take
advantage o our panel data estimation
techniques to measure the unobserved pool
heterogeneity embedded within several earlyperormance measures and then use these
estimates as an exogenous quality metric in
the subsequent net charge-o, prepayment,
and principal payment models.
Finally, the models include a cubic spline
baseline liecycle with our knots5 and inter-
action terms between the spline variables,
current economic conditions, and collateral
type dummies. By introducing these interac-
tions, we measure the dierential impact o
economic drivers on dierent types o assets.
For example, we allow the sensitivity to un-employment rate changes to vary between
pools classied as subprime and those dened
as jumbo deals. Similarly, by interacting the
spline with collateral type, we allow the shape
5 Three in the case o the LGD model.
o the liecycle to depend upon the underlying
quality o the pools under consideration.
Table 2 summarizes the specications
used to model each o the 11 vectors studied
in this article. All the variables (or groups
o variables) are signicant at the 5% level,
and all variables have appropriate signs con-
sistent with economic theory. The models
have been tested rigorously to ensure that
they are optimal, among the set considered,
or orecasting purposes. In Table 3 we pres-
ent the results or one regression, that or
the oreclosure rate, as an example o the
estimation results achieved or all models.
Other specications are, naturally, available
rom the authors on request.
Given that our general model specica-
tion included actors rom all the subcom-ponents described above, we can reasonably
conclude that actors specic and internal
to the pool, together with external mac-
roeconomic actors, are given appropriate
loadings in the calculation o perormance
orecasts. Once we eed in orecasts o
macroeconomic variables derived rom our
structural macroeconomic model, generating
pool-level orecasts is straightorward. Ex-
tending this principle to stress tests which
really constitute little more than pessimistic
economic orecasts is equally simple. Thisprocess delivers a set o vectors under each
alternative macro scenario, including a base-
line projection. The models can be applied
to custom scenarios provided all necessary
macroeconomic variables are covered by the
scenario. The particular shape o these ore-
casts and scenarios depends on the estimat-
ed elasticity o the risk vector to the included
macroeconomic series. As mentioned earlier,
the elasticities have been ound, in many
cases, to be heterogeneous across dierent
collateral groups. Moreover, we nd that
the slopes vary depending on the underlying
quality o the pool in question and the time
at which the pool was originated.
To illustrate these eatures, we present
orecasts and scenarios or a small number o
pools drawn rom the subprime, alt-A, jumbo,
and option ARM collateral types under two
alternative macroeconomic scenarios the
current baseline orecast (a recovery) and an
alternative, depression-like event. These pro-
jections are depicted in Charts 1 and 2. Under
baseline assumptions, we nd that oreclosurerates will stay fat or another quarter as the
real estate market stabilizes and then steadily
decrease as bad accounts move out o the
oreclosure state and are fushed rom the sys-
tem; the vector then converges to the steady-
state baseline liecycle. A depression scenario,
however, generates a sharp double dip, with
gures across collateral types reaching histori-
cally high levels in 2011, similar to the peaks
observed in mid-2009.
A. Out-of-sample validationOne o the most important ndings in the
orecasting literature is that the model that
best ts the data is not necessarily the one
that will provide the most accurate out-o-
sample orecast (Fildes and Makridakis (1995))
Typically, to assess accuracy, the data will be
0
5
10
15
20
25
30
35
07 08 09 10 11 12 13 14 15
Baseline
Alt. Scenario
Chart 1: Projections for Alt-A and Subprime Pools
Foreclosure rates, %
Source: Moodys Analytics
Subprime
Alt-A
0
5
10
15
20
25
07 08 09 10 11 12 13 14 15
BaselineAlt. Scenario
Chart 2: Projections for Jumbo and Option Arm pools
Foreclosure rates, %
Source: Moodys Analytics
Option ARM
Jumbo
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split into two data sets: The rst set, a devel-
opment sample, is used to speciy the model
and estimate its coecients; the second set
is used to evaluate orecast accuracy and is
known as the hold-out sample. To validate
our preerred models, we hold out the last six
available data points at the end o the time
series or each pool. The models were tted
to the remaining historical data. The orecasts
generated using the models were then com-
pared with actual values observed during the
hold-out sample, and aggregate root mean
squared orecast errors were computed.
Underlying our orecast accuracy evalua-
tion was the need to test our preerred mod-
el against reasonable alternatives (Baltagi
(2008)). For this purpose, the out-o-sample
perormance o the HT estimator was com-pared against that o three benchmark mod-
els. Our rst benchmark was a nave orecast
that assumed no change rom the most
recently observed value in the development
sample. The other two benchmarks were
specied similarly to our preerred specica-
tion but were estimated using pooled OLS
and the xed-eects estimator, respectively.
These approaches are described in previous
sections; both should provide ar stier com-
petition to the preerred specication than
the corresponding nave orecast.
Errors or each approach were aggregated
and results presented in Table 4. We present
the perormance o the alternative models
relative to the preerred HT specication.
Numbers greater than unity thereore indi-
cate cases in which the alternative approach
is able to beat the preerred method in a
head-to-head competition.
The results o the validation exercise are
clear-cut. The preerred HT estimated panel
data model suers less squared orecast error
than each o the three considered alternative
specications or all 11 estimated vectors.
The one exception is or charge-os, in which
the xed-eects estimator is able to eke out
a small victory by just a couple o percentage
points. We eel that any test applied enough
times will yield contrary results and placethis nding in that category. Folding in the
act that the xed-eects estimator reduces
model utility, we can easily conclude that a
2% improvement is not enough to warrant a
change in technique.
In terms o the three primary inputs to
the Structured Finance Workstation CDR,
CPR and severity the HT estimated model
easily dominates its competitors and can
thus be recommended. Vectors derived
rom this approach are likely to be optimal in
terms o deriving accurate bond valuations.
Final Remarks
These results demonstrate that pool-leve
perormance aggregates are well orecast us-
ing aggregate panel data specications that
accurately capture the impact o macroeco-
nomic dynamics on the behavior o loans.
The models described are simple, parsimo-
nious structures in which every coecient
estimate can be readily understood using
simple economic intuition. The subsequent
models orecast the aggregate perormance
characteristics accurately and easily lend
themselves to the construction o relevant
stress-testing scenarios.
Structured inance is a complex busi-
ness. Ater the recent recession exposed
the ailure o the models used in the in-dustry, many sought to solve the problem
with even more complex solutions and
models. Though it may seem counterintui-
tive, the correct response to the ailure o
complex models in 2007-2009 was a light
to simplicity and unctionality. The mod-
els that orm the backbone o the Moodys
Analytics system are simple yet compre-
hensive and, importantly, are designed
speciically to tackle the problem o ore-
casting and stress-testing the collateral
underlying ABS deals.
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TABLE 2
Summary o Models inputs
Group Variable
Vector
30 day
delinquency
60 day
delinquency
90+ day
delinquency CDR Bankruptcy Foreclosure REO LGD
Net
Chargeo CPR Principal
Origination
Conditions
LTV X X X X X X X
FICO X X X X X X X X X
Top Originators X X X X X X X X X X X
Vintage Year X X X X X X X X X
Loan Type X X X X X X X X X X X
Economic
Conditionsat
Origination
Fed Funds X X XX (relativeto WAC)
Home Prices X X X X
GDP X
Unemployment Rate X X X X
CurrentEconomicConditions
Disposable Income t, t-3 t, t-3 t-3
Home Prices (HP) t, t-6 t, t-6 t-6 t-3 t, t-6
Change in HP since 0 t t t
Negative Equity Dummy t t t
Unemployment Rate t-3 t-3 t-3 t-1 t-6 t
Avg. Hourly Earnings t-6 t-6 t-6 t-6
GDP t t
Personal Bankruptcies t-6
REFI Volume t-12 t t
Fed Funds tDebt Service Burden t-6 t
Existing Home Sales t-12
Mort. REFI Originations t-12 t
PipelineConnections
30 day delinquency t
90+ day delinquency t-3 t-3 t-3
Bankruptcy t-3
Foreclosure t-1
REO t
Unobserved eect (CDR) X X X
OtherVariables Liecycle * Loan Type X X X X X X
Liecycle * Economic X X X
Loan Type*Economic X X X X
Dec 2005 Bankruptcy Law X
Lifecycle
Number o knots 4 4 4 4 4 4 4 3 4 4 4
Notes: All models include seasonality actors (month) and dummies or zeros
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TABLE 3
Partial Regression Results or Foreclosure Rate
Coefcient Standard Error t-statistic
LTV 0.053 0.004 11.809
FICO (non-linear spline 1) -0.006 0.001 -8.402FICO (non-linear spline 2) -0.001 0.001 -1.889
Unemployment Rate, % at origination -0.443 0.014 -30.842
House Prices, % change year ago lagged 12 months -0.028 0.000 -119.093
GDP, % change year ago -0.015 0.001 -27.163
Dummy indicator or Negative Equity 0.108 0.004 29.156
90+ day delinquency lagged 3 months 0.110 0.001 173.511
Bankruptcy lagged 3 months 0.081 0.001 151.339
Observations 576651
Number o unique pools 11727
Note: model includes liecycle, seasonality, and dummies or zeros, originators, negative equity and loan type and a constant term
TABLE 4
Out o Sample Forecasting Results
Ratio between Hausman-Taylor and benchmark models RMSE
Vector Nave Forecast Pooled OLS Fixed Eects
30 day delinquency 0.935 0.742 0.941
60 day delinquency 0.871 0.853 0.904
90+ day delinquency 0.688 0.479 0.531
CDR 0.830 0.802 0.875
Bankruptcy 0.948 0.720 0.711
Foreclosure 0.572 0.636 0.777
REO 0.973 0.645 0.758
CPR 0.884 0.957 0.993
Principal 0.668 0.586 0.667
Severity 0.911 0.928 0.850
Chargeo 0.762 0.905 1.020
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Reerences
ECONOMIC & CONSUMER CREDIT ANALYTICS
1. Armstrong, J. S. (1985). Long-Range Forecasting: From Crystal Ball to Computer. New York, John Wiley & Sons
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6. Fabbozzi, Frank and Kothari, Vinod, (2008). Introduction to Securitization, Wiley.
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12. Kendall, Leon, and Fishman, Michael (2000). A Primer on Securitization. The MIT Press13. Lutkepohl, H. (2006). Forecasting with VARMA processes, in G. Elliott, C.W.J. Granger & A. Timmermann (eds), Handbook o Economic
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ECONOMIC & CONSUMER CREDIT ANALYTICS
Appendix A: Defnition o Variables
Field Description
Pool Perormance
30 day delinquency Amount o receivables that are 30-59 days past due divided by the original collateral balance (%).60 day delinquency Amount o receivables that are 60-89 days past due divided by the original collateral balance (%).
90+ day delinquency Amount o receivables that are 90 or more days past due divided by the original collateral balance (%).
CDR Constant deault rate based on amount o receivables in deault in the current month, annualized (%)
Bankruptcy Amount o receivables in which the obligor has declared bankruptcy divided by the current collateral balance (%)
Foreclosure Amount o receivables in oreclosure divided by the current collateral balance (%).
REO Amount o receivables that are real estate owned divided by the current collateral balance (%).
Loss-Given Deault (LGD) Monthly net losses during the related monthly period divided by gross losses during the related monthly period (%).
Net Chargeo Net losses during the related monthly period divided by the prior months ending collateral balance (%).
CPR Constant prepayment rate based on unscheduled principal paid by obligors rom the current month, annualized (%).
Principal Total principal collected during reporting period divided by the current collateral balance (%).Pool Origination
LTV Weighted Average Loan To Value at deal origination (%).
FICO Weighted FICO score at deal origination (%).
Top Originators Indicator variables or Top Mortgage originators during the sample time period including Countrywide Bank, WellsFargo, IndyMac, BoA, Citibank, Greenpoint Bank (CapOne), Option One Mortgage, and Residential Funding (GMAC)
Vintage Year Vintage origination year (2001 to 2010)
Loan Type Loan collateral type: Heloc, High LTV, Home Equity/Closed End 2nds, Subprime, Alt-A, FHA-VA, Jumbo, Prime Con-orming, Scratch and Dent, Subprime 2nds, Option Arm
Macroeconomic series
Disposable Income Income: Per capital disposable income, (Constant$, SAAR, annual growth rate)
Home Prices Median Sales Price Existing Single-Family Homes, (Ths. $, SA, annual growth rate)
Change in HP since 0 Dierence in Median Sales Price since Deal Origination (%)
Negative Equity Dummy 1 i change in HP since 0 is negative; 0 otherwise
Unemployment Rate Household survey: Unemployment rate, (%, SA)
Avg. Hourly Earnings Avg. Hrly. Earnings: Total Private, ($ Per Hrs., SA, annual growth rate)
GDP NIPA: Gross domestic product, (Bil. 2000 $, SAAR, annual growth rate)
Personal Bankruptcies Bankruptcies: Personal, Total, (# 3-Month Ending, SAAR, annual growth rate)
REFI Volume MBA: Percent REFI Volume, (%, annual growth rate)
Fed Funds Interest Rates: Federal Funds Rate, (%,P.A.)
Debt Service Burden Debt Service Burden: Total, (% o Disposable Personal Income)
Existing Home Sales Existing Home Sales: Single-Family, (Mil., SAAR, annual growth rate)Mort. REFI Originations Mortgage Originations: Renances, (Mil. $, SAAR, annual growth rate)
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MOODYS ANALYTICS / METHODOLOGY FOR FORECASTING AND STRESS-TESTING ABS AND RMBS DEALS 12
ECONOMIC & CONSUMER CREDIT ANALYTICS
Appendix B: Summary o U.S. Economics Scenarios (July 2010)
Scenario Real GDP Median Home Price Fed Funds Target Unemployment
S1
Stronger Recovery
in 2010
Real growth o 3.9%
in 2010, 4.6% in 2011
Expected to rise 2.9% in
2010 and 2.0% in 2011
The unds rate is
expected to end 2010 at1.6% and 2011 at 2.5%
Peaks at 10.1%
in Q4 2009 andends 2010 at 8.3%
BL Baseline, CurrentReal growth o 2.9%in 2010, 3.6% in 2011
Peak-to-trough declineo 26%, turnaround inmid 2011
The unds rate isexpected to end 2010 at0.2% and 2011 at 1.8%
Peaks at 10.0%in Q1 2011
S2Mild Second
RecessionReal growth o 2.0%in 2010, 1.3% in 2011
Peak-to-trough declineo 36%, turnaround atermid 2011
The unds rate isexpected to end 2010 at0.1% and 2011 at 0.5%
Peaks at 11.8%in Q2 2011
S3Deeper Second
RecessionReal growth o 1.6%in 2010, -0.7% in 2011
Peak-to-trough declineo 40%, turnaround atbeginning o 2012
The unds rate isexpected to remainbelow 1% until Q3 2012
Peaks at 14.0%inQ4 2011
S4Complete Collapse,
DepressionReal growth o 1.3%in 2010, -1.9% in 2011
Peak-to-trough decline
o 45%, turnaround inlate 2012
The unds rate is
expected to end 2010 at0.1% and 2011 at 0.2%
Peaks at 15.1%in mid 2012
S5Aborted Recovery,
Below-TrendLong-Term Growth
Real growth o 2.1%in 2010, 1.8% in 2011
Peak-to-trough declineo 29%, turnaround inmid 2012
The unds rate isexpected to end 2010 at0.1% and 2011 at 0.4%
Peaks at 11.4%in mid 2011
S6Fiscal Crisis, DollarCrashes, Infation
Real growth o 2.2%in 2010, 2.6% in 2011
Peak-to-trough declineo 37%, turnaround inmid 2013
The unds rate isexpected to end 2010 at0.1% and 2011 at 1.9%
Peaks at 13.0%in early 2013, ends2010 at 10.2%
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MOODYS ANALYTICS / METHODOLOGY FOR FORECASTING AND STRESS-TESTING ABS AND RMBS DEALS 13
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