Commercial Mortgage Pricing with Unobservable Borrower Default Costs

This paper develops a pricing model for commercial real estate mortgage debt that recognizes the influence of default transaction costs on the borrower's default decision. These costs are heterogeneous across borrowers and largely un-observable to the lender/investor at the time of origination or loan purchase. A recognition of these unobservable costs can explain why borrower default decisions may differ from those predicted by "ruthless" mortgage-default pricing models. We address the determinants of default choice and timing by replacing sharp default boundaries found in the ruthless models with "fuzzy" boundaries that account for investor uncertainty with respect to evaluating borrower default decisions. To implement our model, we estimate probabilities of default as a junction of time and net equity in the property. Then, given that default occurs, loss severities are modeled based on expected property value recovery net of foreclosure costs and time until the asset is actually sold. Under reasonable parameter value choices, resulting Monte Carlo simulations produce numerical mortgage price estimates as well as component default frequency and severity levels that realistically reflect default premiums and loss levels observed in the marketplace.     

The Termination of Commercial Mortgage Contracts through Prepayment and Default: A Proportional Hazard Approach with Competing Risks

This article examines the factors driving the borrower's decision to terminate commercial mortgage contracts with the lender through either prepayment or default. Using loan–level data, we estimate prepayment and default functions in a proportional hazard framework with competing risks, allowing us to account for unobserved heterogeneity. Under a strict definition of mortgage default, we do not find evidence to support the existence of unobserved heterogeneity. However, when the definition of mortgage default is relaxed, we do find some evidence of two distinctive borrower groups. Our results suggest that the values of implicit put and call options drive default and prepayment actions in a nonlinear and interactive fashion. Prepayment and default risks are found to be convex in the intrinsic value of call and put options, respectively. Consistent with the joint nature of the two underlying options, high value of the put/call option is found to significantly reduce the call/put risk since the borrower forfeits both options by exercising one. Variables that proxy for cash flow and credit conditions as well as ex post bargaining powers are also found to have significant influence upon the borrower's mortgage termination decision.     

Equity Dilution: An Alternative Perspective on Mortgage Default

Empirical research on mortgage default in the single-family market has focused on the value of the borrower's put option using house price indices to estimate contemporaneous loan-to-value ratio or the probability of negative equity. But since the borrower possesses the option to increase leverage by taking on additional debt secured by junior liens subsequent to loan origination (a phenomenon termed here equity dilution ), even a perfect house price adjustment cannot be expected to accurately measure changes in borrower equity over time. Since junior liens are generally unobservable to senior debt holders, proxies are required in empirical applications. This paper employs an independent estimate of junior lien probability developed from the 1998 Survey of Consumer Finances combined with loan level mortgage performance data to examine the role junior liens play in increasing default risk.     

A Simple Model of Mortgage Insurance

This paper uses a two-period model to analyze the borrower's choice of an optimal time pattern of mortgage payments in a world where future house values are uncertain. Since a decline in values can make the borrower's equity negative, leading to default on the mortgage, lenders in the model will require the purchase of mortgage insurance. The premium on the insurance policy will depend on the riskiness of the mortgage, which in turn depends on the magnitude of the initial mortgage payment. Mortgages with large (small) first payments will carry low (high) insurance premiums. Taking this fact into account, the borrower decides on the optimal riskiness of his mortgage. Borrowers who discount the future heavily choose risky mortgages carrying high insurance premiums, while those who place a higher value on future consumption opt for less risky contracts carrying low (or zero) premiums.     

Predicting Commercial Mortgage Foreclosure Experience

This study has two objectives: (1) it directly evaluates the relationship between commercial mortgage default incidence and characteristics of the mortgage, borrower, property, market, and general economic conditions, and (2) it uses this relationship to predict the exposure of life insurers to future mortgage defaults and to examine the relative importance of various causes of current and past credit quality problems. A theoretical model of the default decision predicts that the decision would be expected to be driven primarily by the borrower's current equity stake in the property, or the ratio of the market value of the loan to property value (M_t/V_t), but that the presence and magnitude of transaction costs associated with default would be expected to result in underexercise of the default option. Empirical estimation making use of American Council of Life Insurance (ACLI) and National Council of Real Estate Investment Fiduciaries (NCREIF) data confirms both expectations. A high proportion of the longitudinal variation in foreclosure incidence is explained by variations in M_t/V_t, but even at high ratios M_t/V_t in excess of 1.1. only 5% to 8% of mortgagors default, although this magnitude of underexercise is probably overstated because of problems in measuring M^t and for other reasons. Simulations using the model provide a pessimistic outlook for future defaults. Default rates are predicted to double in the five-year period 1988–93. Other simulations examine the relative importance of interest rate fluctuations, property value declines, and geographic or temporal correlations in lending during the 1976–88 period on current default experience.     

Equity and Nonequity Determinants of FHA Single-Family Mortgage Foreclosures in the 1980s

We examine foreclosures on FHA single-family mortgages insured during the 1975–87 period. The importance of the market value of borrower equity and national house price dispersion support much earlier work emphasizing the key role of negative equity in triggering default. The lower is "mean" market-value equity, and the greater is dispersion, the greater is the fraction of borrowers likely to have negative equity. The unemployment rate and the book value of borrower equity are also shown to be significant determinants of default. Unemployment is one of those events that can force borrowers to move. The moving decision increases the likelihood of default because moving costs no longer deter default, and the costs of selling the house reduce the effective equity in the house. The book value of equity is relevant to this decision because it is what the sellers receive if they move without defaulting. Not only are both of these variables significant determinants of default, but the smaller is book equity, the greater is employment impact (with large book equity, unemployment should not matter because selling the house is preferred to default).     

Privatized Default Risk and Real Estate Recessions: The U.K. Mortgage Market

A mortgage pricing model is developed when a borrower goes through a series of distress states, including delinquency, long-term nonpayment and ultimate default. These steps are sequential, and depend on prices and alternatives faced by the borrower. The multistate default model is applied to the mortgage market in the United Kingdom. As a byproduct, a pricing structure for the U.K. endowment mortgage, which combines a good and a life insurance policy, is developed. Income and liquidity constraints are shown to affect the decision to keep a mortgage current in different states of distress. Solvent borrowers may thus keep their mortgages current, even when equity is negative.     

Valuing the Defeasance Option in Securitized Commercial Mortgages

To protect the interests of investors, commercial mortgage loans pooled for the issuance of commercial mortgage-backed securities (CMBS) have restrictive covenants that discourage the borrower from refinancing. Such restrictions limit the borrower's ability to access any accumulated equity. The predominant means of accessing this equity today is defeasance. By defeasing a loan, the borrower substitutes the commercial mortgage with U.S. Treasury or agency obligations whose payments match those of the defeased mortgage. Therefore, defeasance is an exchange option whereby the borrower gives up the portfolio of Treasury or agency securities and in return receives the market value of the commercial mortgage plus the liquidity benefits arising from accessing the accumulated equity in the underlying property. The value of the option to defease is shown to depend critically on the rate of return that can be earned on the released equity, prevailing interest rate conditions, as well as the option's contractual features.     

The Impact of Interstate Foreclosure Cost Differences and the Value of Mortgages on Default Rates

Previous research on mortgage default has focused on the costs, benefits, and characteristics of the mortgagor. In such studies default rates have been taken as a measure of mortgage risk. In this paper we present a model where the position of the lender affects the default-foreclosure process. Important to the lender's decision to foreclose rather than renegotiate an existing loan are the value of mortgage and the legal costs associated with foreclosure.
The empirical evidence supports the hypothesis that both the value of the mortgage and legal foreclosure costs affect the foreclosure rate. In those states where legal foreclosure costs are high rates are significantly less than where costs are low. This suggests that previous models which include only the costs and benefits of default to the borrower are incomplete and that foreclosure rates can not be taken as a strict measure of mortgage risk. That is, low foreclosure rates may indicate that losses occur in other forms of loan negotiation rather than in expensive legal costs.     

Estimation of Mortgage Defaults Using Disaggregate Loan History Data

This paper addresses, theoretically and empirically, the structure of influences affecting the default option in mortgage contracts. A formal theoretical model recognizes that a number of loan and non-loan related effects beyond equity in the unit could influence the default decision. These include 1) payment levels relative to income, which could displace other investment opportunities or cause a need for borrowing or sale to meet mortgage obligations; 2) current and expected neighborhood and housing market conditions, in particular the expected relative rate of appreciation of the unit and the relative cost of homeownership; 3) economic conditions; 4) wealth; 5) borrower characteristics proxying for variability in income or "crisis" events; as well as 6) transactions costs incurred upon default. Estimates of the model making use of a micro-level sample of individual loan histories over a twelve year period, supplemented by longitudinal census and economic information, find a number of these "other" effects important. Simulations find several of them to dominate the equity effect on default and to help explain why some households with zero or negative equity may not default, while others with positive equity may. The implications of these results for appropriate specification of the pricing model describing the default option and for appropriate underwriting of AMIs are noted.     

Industrial Real Estate Mortgage Default Experience of the New York State Job Development Authority Second Loan Program: A Preliminary Investigation

This paper explores the loan loss experience of a public industrial lending authority, employing contemporaneous borrower net equity as a link to mortgage loan default. The relationship between default, net equity and bankruptcy is tested on a small longitudinal data set of loans using nonparametric statistics and a proportional hazard model. Results show that negative net equity and firm bankruptcy are strongly associated with default among the study population. Further, the borrowers studied did not exercise the put option promptly, suggesting potential benefits from monitoring net equity one year or more prior to default.     

Do Riskier Borrowers Borrow More?

Conventional wisdom in the mortgage industry holds that loan-to-value (LTV) ratios are positively correlated with mortgage default rates. However, not all empirical studies of mortgage loan performance support this view. This paper offers a theoretical signaling model of why the correlation between LTV ratios and default risk is contingent upon the default costs of the borrower. Specifically, the model proposes that when default costs are high there exists a separating equilibrium in which risky borrowers will self-select into lower LTV loans to reduce the probability of facing a costly default, while safe borrowers will self-select into higher LTV loans as a signal of their enhanced creditworthiness. This adverse selection process gives rise to the possibility of higher default probabilities for lower LTV loans. Conversely, when default costs are low the conventional result, in which risky borrowers select higher LTV loans than safe borrowers, is obtained. Empirical results, based on a sample of 859 single-family residential mortgage loans drawn from the portfolio of a national mortgage lender, are consistent with the separating equilibria predicted by the model.     

Explaining Refinancing Decisions Using Microdata

This paper develops a model which explains how mortgage-rate movements, transactions costs, changes in borrower income and house value, personal financial opportunities and the prepayment option embedded in fixed-rate mortgages affect a financially flexible borrower's decision to refinance an existing loan while retaining the underlying home. Broadening the focus of previous analytical work, the model explains why households with similar mortgage loans may react differently as financial market conditions change. It contains definitive empirical predictions that are supported by an analysis of a choice-based sample of individual loan transactions. Results suggest that refinancings are motivated both by movements in the level of interest rates and by borrowers' desires to alter their capital structures in the face of changing income and housing wealth.     

Modeling the Conditional Probability of Foreclosure in the Context of Single-Family Mortgage Default Resolutions

Both empirical and pricing-simulation models of mortgage default focus on foreclosure in a one-step decision framework. Such models are misspecified to the extent that mortgage default and foreclosure are two separate decisions or events, where foreclosure is but one outcome of a default episode. This study examines the dynamics of mortgage borrower default episodes using a large sample of FHA-insured single-family mortgages. We estimate the influence of borrower characteristics, mortgage terms, and economic conditions on probabilities of various resolutions, highlighting under what conditions foreclosure is more likely to result from mortgage default.     

Waiting to Default: The Value of Delay

This paper analyzes the opportunity for early termination of a mortgage contract. We consider the possibility of defaulting on the property and explore the rules that are used by a value-maximizing borrower in exercising this option to default. The discussion centers on the value of waiting to make such a decision and the consequences of this rational inertia. We show that the observed delay in default usually attributed to transaction costs can instead be explained as entirely rational choice in a dynamic environment.     

Optimal Mortgage Refinancing with Stochastic Interest Rates

The purpose of this paper is to develop a dynamic model of mortgage refinancing in a contingent claim framework that simultaneously solves for the borrower's optimal mortgage refinancing strategy, the value of the refinancing call option, the value of the mortgage liability to the borrower, and the market (lender) value of the fixed-rate contract. We also calculate the minimum differential between the contract rate on the existing mortgage and the current interest rate that is required to trigger an optimal mortgage refinancing.     

Reverse Mortgages: Contracting and Crossover Risk

A pricing model is developed for a reverse mortgage contract where the borrower receives payments either as a lump sum or in an annuity while the loan balance accumulates as a claim against the house. No underwriting criteria on income are applied. One risk of default is that the borrower will remain in the house after the negatively amortizing loan balance exceeds the value of the house. An explicit pricing model of the reverse mortgage permits the evaluation of this default "crossover" option. Alternative methods involving life insurance contracts and securitization are compared as secondary market channels.     

Stochastic Modeling of Federal Housing Administration Home Equity Conversion Mortgages with Low-Cost Refinancing

Federal Housing Administration-insured reverse mortgages, known as Home Equity Conversion Mortgages (HECMs), did not originally have a provision for low-cost refinancing. If a borrower's house value increased faster than expected, the borrower could not tap that additional equity without terminating the first loan and originating a new HECM loan with full closing costs. We test several low-cost refinancing options using a stochastic simulation model that allows interest rates and house prices to vary in historically accurate patterns. Low-cost refinancing decreases the net value of the fund by 54% to $98.5 million, but it remains positive in 80% of the trials.     

Mortgage Borrower Repayment Behavior: A Microeconomic Analysis with Canadian Adjustable Rate Mortgage Data

In this paper we estimate a model of mortgage borrower behavior using micro-level data on Canadian borrowers with rollover mortgages—a form of adjustable-rate mortgage. Our results suggest that the probability of default rises with a decrease in housing equity and an increase in the mortgage contract rate; however the size of these changes is relatively small. They also show that partial prepayment is sensitive to fluctuations in the rates of return from investing in housing versus other assets. For the United States experience, our results suggest that, relative to fixed-rate mortgage borrowers, adjustable-rate mortgage borrowers are more likely to default and less likely to prepay.     

Closed-Form Mortgage Valuation Using Reduced-Form Model

Valuing mortgage-related securities is more complicated than valuing regular defaultable claims due to the borrower's prepayment behavior as well as the possibility of default. Some researchers use a structural-form model to obtain the closed-form formulas for the mortgage value. With this method, however, it is difficult to identify the critical region of early exercise. As an alternative, the reduced-form model developed in this article is able to value the mortgage without setting boundary conditions, and it can thereby accurately handle the multidimensional space of correlated state variables. The purpose of this article is to derive a closed-form solution of the mortgage valuation equation under a general reduced-form model that embeds relevant economic variables. This new approach enables portfolio managers to undertake sophisticated portfolio optimization and hedging analyses. An implementation procedure for the model is also provided to demonstrate how the valuation framework can be utilized in practical applications.