The S-Curve

Welcome to The S-Curve

Now you will be able to receive the latest announcements, product updates, and our insights on the mortgage market in real time.

The name of the blog, the S-Curve, is a reflection of our logo and the central feature of our prepayment model. S-curves are seen in nature in many phenomenon, from population growth to prepayment and default models. Our first S-curve, in the early 1990s, used the arctangent function, then piece-wise linear functions, and evolved over time to be more complex and vary by FICO, loan size and LTV. This evolution encapsulates both the timeless nature of fundamental relationships and constant innovation to describe them better over time.

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Blog - Latest
  • Federal Home Loan Bank of San Francisco's Innovations in Mortgage Finance Symposium

    Richard Cooperstein

    Events

    The Federal Home Loan Bank of San Francisco directed the Urban Institute to develop innovative and actionable ideas to close the gap between white and black homeownership rates, which is as wide today as before the Fair Housing Act, enacted 60 years ago. Homeownership is crucial to a fairer society because working and middle-class families most commonly create inter-generational wealth by owning homes with amortizing mortgages. Urban Institute’s eighteen-month effort culminated in a symposium in February in Los Angeles attended by dozens of housing experts. The Borrowers Mutual Escrow Fund (BMEF), which I developed a few years ago, was included in the Urban Institute study, and I was invited to discuss it at the symposium.

    A few key themes emerged from the symposium. One centers around replacing decades-old credit scores with modern metrics that better reflect borrower financial condition as the consumer financial footprint has become increasingly digitized, especially among minority populations. These metrics generally extend beyond traditional credit profiles to include other important measures of borrower financial condition such as digitized cash flow data, telecom/utility data and others. A fair amount of evidence already shows that modernized metrics assess homeownership readiness much better than old ones. Reducing uncertainty reduces cost.

    Another theme that includes the BMEF, is that when trying to expand homeownership, liquidity and cash flow stability can be more critical to the success of marginal borrowers than traditional credit scores and down payments. Conscientious borrowers generally strive to restart paying their mortgages after short delinquencies if given the chance. Empirical support for this view includes delinquency performance through repeated climate events (e.g., hurricanes and floods) and the success of generalized forbearance during the COVID-19 pandemic.

    This has turned decades of loss mitigation wisdom on its head. The Massachusetts state mortgage insurance program has included unemployment benefits for almost 20 years to resounding success. This program provides borrowers with fragile liquidity and volatile income, with a few months of payment reserves between jobs (e.g., consistently succeeds in preventing delinquency even through the financial crisis of 2007 and the COVID-19 pandemic). The GSEs and FHA have now made forbearance their initial loss mitigation response to borrower delinquency.

    The BMEF proposes that borrowers put 3% of their house value into an administered escrow account instead of towards a down payment. It’s well-known that reserves are crucial to borrower success and placing reserves into escrow to be used for income interruption or unexpected maintenance will make reserves even more effective. Money in such accounts will always reduce risk compared with small down payments for borrowers, servicers, mortgage insurers and guarantors. This is provably true because the escrow funds are very liquid for payments, while the liquidity value of small down payments is effectively zero. Further evidence is that reperformance rates for delinquent borrowers are higher for borrowers with lower credit scores than for those with higher credit scores.

    Borrowers pay mortgage insurance and guarantee fees to compensate insurers for risk, but it does not impact borrower ability to pay. By contrast, putting aside borrower funds for financial stress reduces risk throughout the value chain. Since it is borrower money in the first place, no subsidy is needed, but risk declines because liquidity is improved. Finally, borrower escrows managed by servicers for taxes and insurance are individual. However, BMEF escrows can be combined across borrowers to generate large diversification gains. Even among traditionally risky borrowers, perhaps 75% of them will never become delinquent, so it’s likely that the benefit limit can exceed the average contribution.

Blog - Archives

The S-Curve Archives

  • Richard Cooperstein

    Thoughts

    Summary

    In 2021, Andrew Davidson & Co. Inc. (AD&Co) proposed a benchmark cohort approach to setting Ability-to-Repay (ATR) Qualified Mortgages (QM) standards. Successful benchmarks based on data are model-free and transparent, and the cohorts must perform consistently in comparison to one another and across time. Our original work used data through the early stages of the pandemic when non-performing loan percentages skyrocketed.

  • Richard Cooperstein

    Thoughts

    How Lowering Capital Costs Affects Higher-Risk Loans

    Government-sponsored enterprises (or GSEs) are companies that provide guarantees and financing to originators through the mortgage secondary market. The size and resilience of the GSE secondary market maximizes diversification and liquidity which reduces financial risk and cost of capital. This benefit accrues to conforming borrowers through lower mortgage rates and resiliently available financing. 

  • Alex Levin

    Products

    The release of Andrew Davidson & Co., Inc.’s (AD&Co) new generation of financial engineering tools marks a shift to a new reality; when the traditional benchmark for MBS valuation, the LIBOR/ Swap yield curve, becomes unavailable. Our recent Product Release email informed our readers about the change. In short, our users can:

  • Richard Cooperstein

    Thoughts

    FHFA held a listening session for interested parties on its proposed rule on the GSE process for credit scores.  The objective is making mortgage underwriting and pricing more accurate and more fair while balancing practical implementation by firms in the mortgage ecosystem.  Along with many others, I had the opportunity to provide insights on this proposed rulemaking.

  • Andrew Davidson

    Thoughts

    In our January 19th blog entitled, A More Equitable Lending System Will Not Be Created by Accident, we described the efforts it will take to overcome not just bias in lending today, but the systemic factors that have limited access to credit in the past and have created an unjust system. 

  • Eknath Belbase

    Thoughts

    In this short blog post I discuss some developments taking place in the flood insurance landscape in the US and look ahead at a few potential directions things could go. I suggest that universal catastrophic flood insurance coverage with a continuation of the introduction of risk-based pricing would be a significant improvement.

  • Richard Cooperstein

    Thoughts

    Introduction

    The Government-Sponsored Enterprises (GSEs) entered conservatorship in September 2008. One could view the succeeding thirteen years as a journey back to financial stability with a refined operating model that looks more like a financial utility than a hedge fund. This business model is more compatible with a fair lending mission for a standard-setter that maintains secondary markets under an effective regulator. The GSEs remain the largest part of the housing finance backbone and a resilient funding source during economic stress.

  • Andrew Davidson

    Thoughts

    Around 75% of white American families were homeowners in the first quarter of 2020, according to data from the United States Census Bureau. However, only 44% of Black American families owned their homes at the same time.

  • Eknath Belbase

    Thoughts

    According to a report by the Research Institute for Housing America, climate change risk is rapidly increasing in the housing industry and will continue to demand more attention and regulation in the near future.

  • Mickey Storms, Richard Cooperstein

    Thoughts

    Mortgage market participants are keenly aware that the Federal Reserve has been scaling back its UST and MBS purchases and factoring the outcomes of its actions on stakeholders across markets.