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2012 Valuation Actuary Symposium
Sept. 10- 11, 2012
Session #49 PD: Introduction to
Asset Modeling Concepts
Yidong Liu, FSA, MAAA
Gregory J. Roemelt, FSA, MAAA
Moderator
Guillaume Briere-Giroux, FSA, MAAA
Primary Competency
Technical Skills & Analytical Problem Solving
Introduction to Asset Modeling 1
Tuesday, September 11, 2012Valuation Actuary Symposium
ASSET MODELING
1
Greg RoemeltWinter Liu
September 11, 2012
Need for Asset Models
§ Cash flow testing§ ALM work§ Financial plan§ Capital planning§ RBC calculations § SOP 03-1§ Principle based reserves
2
Introduction to Asset Modeling 2
Tuesday, September 11, 2012Valuation Actuary Symposium
Purpose of Session
§ Agendaú Building blocks of asset modelsú Common asset classes and modeling
considerationsú Reinvestment / disinvestment
§ Exclusionú Only focus on the general accountú Will not include a discussion of interest rate or
equity scenario generators
3
Fundamental Asset Components
§ An asset model tracks three fundamental components of any underlying assets
ú Interest§ Coupon
frequency§ Coupon rate§ Reference
rate
ú Principal§ Scheduled
amortization§ Call / put /
prepayment§ Default§ Maturity§ Sales
ú Value§ Par§ Book§ Market
4
Introduction to Asset Modeling 3
Tuesday, September 11, 2012Valuation Actuary Symposium
Fundamental Asset Components
§ An asset model tracks three fundamental components of any underlying assets
ú Interest§ Coupon
frequency§ Coupon rate§ Reference
rate
ú Principal§ Scheduled
amortization§ Call / put /
prepayment§ Default§ Maturity§ Sales
ú Value§ Par§ Book§ Market
5
Asset Class Yield Curves
§ Use of asset yield curvesú Calculate market valueú Determine yields on reinvestmentsú Basis for exercise of financial options
§ Model asset yield curvesú Treasury yield curve + asset spread
6
Introduction to Asset Modeling 4
Tuesday, September 11, 2012Valuation Actuary Symposium
Model Asset Yield Curve
§ Treasury yield curve § Published daily§ Can be modeled deterministically or stochastically
§ Asset spreads are the incremental amounts added to treasury rates to get the yields for risky assetú Readily available for frequently traded assetsú Vary by various risk factorsú Typically modeled deterministicallyú Typically use initial spreads based on market
conditions and grade to long term averages
7
Asset Spreads Vs. Treasury
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BBB Bond
10yr Treasury
Introduction to Asset Modeling 5
Tuesday, September 11, 2012Valuation Actuary Symposium
Asset Spreads Consideration
§ Credit rating§ Maturity§ Liquidity§ Embedded optionú May be more difficult to develop
9
Sample Bond Credit Spreads
AA A BBB90-Day 95 125 1401-Yr 120 150 1602-Yr 130 160 1753-Yr 140 170 1905-Yr 150 180 21010-Yr 160 190 23030-Yr 190 220 260
10
Introduction to Asset Modeling 6
Tuesday, September 11, 2012Valuation Actuary Symposium
Asset Default
§ Vary by asset class and credit rating§ Level or by durationú Level: could vary by years to maturityú Duration: increasing rates with age
§ Probability times severity§ “Fallen Angels”
11
Model Defaults
§ Modeled as a reduction in book valueú 20 bps annual default assumption translates to
a 0.2% annual reduction in book value
§ Modeled as a reduction to investment incomeú 5.25% coupon with a 20 bps annual default
assumption generates 5.05% income
§ Deterministic vs. Stochastic§ Linked to interest rate?
12
Introduction to Asset Modeling 7
Tuesday, September 11, 2012Valuation Actuary Symposium
Default Assumption
§ Default assumption – sources of dataú Moody'sú S&Pú Wall streetú Company experience/investment advisors
13
Asset Classes
ú Non-callable bondsú Callable bondsú Inflation indexed bondsú Mortgages and mortgage pass-through'sú Collateralize mortgage obligations (CMOs)ú Asset Back Securities (ABS)ú Collateralize debt obligations (CDOs)ú Derivatives
14
Introduction to Asset Modeling 8
Tuesday, September 11, 2012Valuation Actuary Symposium
Non–Callable Bonds
§ Required dataú Book value (Stat, tax, GAAP)ú Par valueú Maturity dateú Coupon – rate and modeú Sinking fund schedule
§ Other useful dataú CUSIPú Market value
15
Non–Callable Bonds – Cash Flows
§ Fairly simple to project§ Interest paymentú At coupon date: Cash Flow = Par x Coupon / Mode
§ Principal paymentú If sinking fund date, scheduled amountú At maturity, Par
16
Introduction to Asset Modeling 9
Tuesday, September 11, 2012Valuation Actuary Symposium
Non–Callable Bonds – Cash Flows
Date Par – BOY Coupon Sinking Fund Total CF
12/31/2008 $10,000 $500 $2,000 $2,500
12/31/2009 $8,000 $400 $2,000 $2,400
12/31/2010 $6,000 $300 $2,000 $2,300
12/31/2011 $4,000 $200 $2,000 $2,200
12/30/2012 $2,000 $100 $2,000 $2,100
17
Non–Callable Bonds –Investment Income§ Cash flow§ Change in investment income due & accrued§ Amortization of premium/accrual of discountú Yield is not equal to coupon if book not equal to
par
18
Introduction to Asset Modeling 10
Tuesday, September 11, 2012Valuation Actuary Symposium
Non-callable bonds – Investment Expenses§ Sources of assumption ú Annual Statement – Exhibit 2ú Investment advisors
§ May vary by asset categoryú Bondsú Mortgagesú Real estateú Policy loans
19
Non-callable Bonds – Market Values§ Present value of future cash flows§ Based on assumed asset category yieldú Treasury yield + asset spreadú Yield and spread tied to average life
§ Market value calibrationú Calculated MV likely differs from reported MVú Additional spread calculated to calibrateú Ignore, maintain or grade additional spread
20
Introduction to Asset Modeling 11
Tuesday, September 11, 2012Valuation Actuary Symposium
Callable Bonds
§ Similar to non-callable, except issuer of the bond has the right (option) to call (pay off) the bond at some future date(s)§ May be callable at a point in time (European
option), or may be callable over a period of time (American option)§ May be a “call premium”
21
Callable Bonds
§ Higher coupon than comparable non-callable bond§ Difference is price of call option§ Purchaser of bond has sold a call option to
issuer of the bond
22
Introduction to Asset Modeling 12
Tuesday, September 11, 2012Valuation Actuary Symposium
Callable Bonds – Cash Flows
§ If bond is not called, identical to non-callable§ Call behaviorú Driven by interest ratesú Present value of cash flows at current rates VS.
call price plus any refinancing costú The more “in the money” the call, the more likely
the bond will be calledú Easier (or cheaper) for high grade lenders to
refinance
23
Callable Bonds – Market Values
§ Much more difficult to calculate§ Include the price of the call option§ No closed form solutions for American calls§ Multiple scenario / binomial lattice
methodology
24
Introduction to Asset Modeling 13
Tuesday, September 11, 2012Valuation Actuary Symposium
Treasury Inflation-Protected Securities (or TIPS)
§ Coupon is fixed§ Principal adjusted to the Consumer Price
Index
25
Mortgages
§ Property typeú Commercialú Residential
§ Amortization Patternú Amortizingú Non-Amortizing (interest only)ú Balloon
§ Interest Rateú Fixedú Floating
26
Introduction to Asset Modeling 14
Tuesday, September 11, 2012Valuation Actuary Symposium
Quality of Underwriting –Residential Mortgages§ Conforming mortgage ú Strict standards Amount Down payment Income Credit history Property condition
§ Non – conforming loansú Alt-Aú Subprime
27
Mortgages – Cash Flow
§ Interest only – identical to bullet bond§ Amortizing – Payment to amortize ú Loan period for non-balloonú “Amortization period” for balloonú Payment recalculated for ARM
28
Introduction to Asset Modeling 15
Tuesday, September 11, 2012Valuation Actuary Symposium
Outstanding Principal
0%10%20%30%40%50%60%70%80%90%
100%
0 3 6 9 12 15 18 21 24 27 30
Period
Pri
ncip
al
29
Outstanding Principal
Period
Cas
h Fl
ow
Interest Principal Total
30
Introduction to Asset Modeling 16
Tuesday, September 11, 2012Valuation Actuary Symposium
Prepayments
§ Mortgagees frequently have the right to pay off or “prepay” mortgage§ Residential – usually no prepayment penalty§ Commercial – lock out period and “Make
Whole” provisions
31
Factors Influencing Prepayments§ Refinancing incentiveú Current rate VS. market rate + refinancing cost
§ Age of the mortgage§ Seasonality§ Burnout
32
Introduction to Asset Modeling 17
Tuesday, September 11, 2012Valuation Actuary Symposium
Public Securities Assoc (PSA) Prepayment Model§ Increasing prepayment amounts for 30
months§ Constant thereafter at 6.0% per year§ Not based on hard data§ Used as industry standard pattern
33
100% PSA
0%
1%
2%
3%
4%
5%
6%
7%
Months
Con
stan
t Pre
paym
ent Rat
e
34
Introduction to Asset Modeling 18
Tuesday, September 11, 2012Valuation Actuary Symposium
Principal Payments – 100% PSA
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
Pri
ncip
al P
aym
ents
Month
35
Mortgages – Market Value Calculations§ Can be pricing using a constant PSA§ Monte Carlo techniques more robust but
more time consuming§ “Model” similar mortgages to develop a
market to book ratios, apply to all modeled§ Outside systems
36
Introduction to Asset Modeling 19
Tuesday, September 11, 2012Valuation Actuary Symposium
Mortgage Passthrough Securities§ An asset-backed security whose cash flows
are backed by the principal and interest payments of a set (pool) of mortgage loans§ Holders of MBS share proportionally in the
cash flows of the mortgage pool
37
Description of Pools
§ Type of collateralú Agencyú Whole loan
§ Weighted Average Coupon (WAC)ú Average of all the coupons in the mortgage pool,
weighted by principalú Will tend to decrease over timeú Always higher than the “passthrough rate”
§ Weighted Average Maturity (WAM)ú average of the maturities of the mortgages in the pool
38
Introduction to Asset Modeling 20
Tuesday, September 11, 2012Valuation Actuary Symposium
Modeling MBS
§ Similar to modeling regular mortgages§ Default assumptions different if agency
backed§ Careful to model prepayments based on the
weighted average coupon and not the passthrough rate
39
Collateralize Mortgage Obligations (CMOs)§ A CMO is essentially a way to create many
different kinds of bonds from the same mortgage pool so as to please many different kinds of investors.§ CMO is a Special Purpose Entityú Legal owner of a set of mortgages, called a pool.ú Investors buy bonds (tranches) issued by the entityú Payments to the investors made based on a defined
set of rules, called the structure
40
Introduction to Asset Modeling 21
Tuesday, September 11, 2012Valuation Actuary Symposium
Types of CMO Tranches
§ Sequentials§ PACs/TACs§ Z tranche§ Principal Only§ Interest Only
41
Sequential CMOs
§ First CMOs§ Pay principal sequential to tranches§ Purpose was to create short, medium and
long term out of a single mortgage pool
42
Introduction to Asset Modeling 22
Tuesday, September 11, 2012Valuation Actuary Symposium
Sequential CMOPrincipal Payments – 100% PSA
0.0
1.0
2.0
3.0
4.0
5.0
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7.0
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ncip
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aym
ents
Month
43
Principal Payments 100% and 350% PSA
0.0
2.0
4.0
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aym
ents
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PAC Schedule 100% PSA 350% PSA
44
Introduction to Asset Modeling 23
Tuesday, September 11, 2012Valuation Actuary Symposium
Principal Payments – 100 PSA
0.0
2.0
4.0
6.0
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10.0
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14.0
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20.0
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ncip
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aym
ents
Month
PAC Support
45
Principal Payments – 350 PSA
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
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18.0
20.0
Pri
ncip
al P
aym
ents
Month
PAC Support
46
Introduction to Asset Modeling 24
Tuesday, September 11, 2012Valuation Actuary Symposium
Principal Payments – 600 PSA
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
18.0
20.0
Pri
ncip
al P
aym
ents
Month
PAC Support PAC Schedule
47
Principal Payments – 50 PSA
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
18.0
20.0
Pri
ncip
al P
aym
ents
Month
PAC Support PAC Schedule
48
Introduction to Asset Modeling 25
Tuesday, September 11, 2012Valuation Actuary Symposium
PACs – Cash Flow Priorities
§ Model cash flows of underlying mortgage pool§ Allocate principal payments to “Most Protected”
PAC§ Allocate principal payments to “Less Protected”
PAC § If principal remaining, allocate to support
tranches§ If principal remaining, allocate to “Less
Protected” PAC§ If principal remaining, allocate to “Most
Protected” PAC
49
Asset Backed Securities
§ Home Equity Loans§ Auto Loans§ Manufacture Housing§ Credit Cards§ Student Loans§ Equipment Leases§ Other Assets
50
Introduction to Asset Modeling 26
Tuesday, September 11, 2012Valuation Actuary Symposium
Modeling CMO & ABS
§ Key considerationú CMOs tranche prepayment riskú ABS tranche default riskú Model underlying collateralú Allocate principal based on structure
§ Typically difficult to model in-house
51
Collateralized Debt Obligations (CDOs)§ Similar to ABS, but collateral is a wide variety
of financial instruments§ Modeling strategy is the same:ú Project cash flows of underlying collateralú Use CDO structure to parse cash flows amongst
various classes within the CDO
§ Complexity Risk
52
Introduction to Asset Modeling 27
Tuesday, September 11, 2012Valuation Actuary Symposium
Types of CDOs
§ Structured finance securities (mortgage-backed securities, home equity asset-backed securities, commercial mortgage-backed securities)
§ Leveraged loans § Corporate bonds § Real estate investment trust (REIT) debt § Commercial real estate mortgage debt (including whole
loans, B notes, and Mezzanine debt) § Emerging-market sovereign debt § Project finance debt § Trust Preferred securities
53
Interest Rate Derivatives
§ Notional amount applied to some combination of reference rates and strike rates§ Cap: Notional x max ( reference rate - strike
rate, 0 )§ Floor: Notional x max ( strike rate – reference
rate, 0 )§ Swap: Notional x [ reference rate(1) –
reference rate(2) ]
54
Introduction to Asset Modeling 28
Tuesday, September 11, 2012Valuation Actuary Symposium
Equity Derivatives
§ Typically only modeled for specific products (e.g., FIA)§ Pricing difficult§ Options/derivatives as a reinvestment asset
55
Validation of Asset Models
§ Starting valuesú Bookú Parú Market
§ Portfolio Yield§ Cash flow analysisú Principal paymentsú Interest paymentsú Calls/Prepaymentsú Defaults
§ Policy loans
56
Introduction to Asset Modeling 29
Tuesday, September 11, 2012Valuation Actuary Symposium
Typical Modeling Approach by Asset Class§ Model seriatim in-houseú Bondsú Mortgages & mortgage pass-throughú Interest rate derivativesú Simple European equity options
§ Model via external vendors (EPA)ú CMOú MBSú CDO
57
Asset/Liability Interaction
§ Reinvestment§ Disinvestment
58
Introduction to Asset Modeling 30
Tuesday, September 11, 2012Valuation Actuary Symposium
Reinvestment Strategies -Basic§ Define asset mixú Asset classú Credit ratingú Maturity
§ Rebalanceú No - Cash methodú Yes - Book method
59
Reinvestment Strategies -Conditional§ Change over projection horizonú E.g., invest in longer average duration in first five
years, then shorter duration thereafter
§ Scenario drivenú E.g., invest in longer average duration when yield
curve is normal (i.e., upward sloping) and switch to shorter duration when yield curve is inversed
§ Duration matchú Keep average asset duration within tolerance level
to average liability duration60
Introduction to Asset Modeling 31
Tuesday, September 11, 2012Valuation Actuary Symposium
Reinvestment Strategies –Duration Match§ Determine liability durationú Pre-specifiedú Dynamically calculated
§ Define tolerance & frequency§ Define “duration match” portfolioú Long vs. shortú Asset class (e.g., bonds, interest derivatives)
§ Allow rebalance?
61
Reinvestment Strategies –Duration Match
Liability duration = Existing asset duration x Weight1 + “Match portfolio” duration x Weight2
§ No rebalance: 0 < Weight2 < cash available§ With rebalance: 0 < Weight2 < 1
62
Introduction to Asset Modeling 32
Tuesday, September 11, 2012Valuation Actuary Symposium
Disinvestment Strategies
§ Selling assetsú Market value calculationsú Order of sales Existing vs. reinvested (or “model purchased“) By asset class – e.g., sell easier-to-value assets Pro rata vs. single assets (e.g., maximize gain)
§ Buying negative assets (borrowing from another Line of business)§ Borrowing
63
Questions?
64