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.

We hope you find the information useful and we look forward to your feedback.

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Blog - Latest
  • Gritty Renaissance: AD&Co Visits Detroit

    Tom Parrent

    Thoughts

    AD&Co held our annual employee meeting in Detroit, Michigan. In addition to gathering everyone in person to socialize and strategize, we use these annual meetings to learn about different cities, especially with regard to housing market dynamics.

    We chose Detroit because the oft-maligned city is undergoing a significant renaissance, and we wanted to explore the area and learn how housing may have played a role in both Detroit’s decline and rebirth.

    From the early 1900s through the mid-1960s, Detroit was an industrial and innovation powerhouse. Beyond automobiles, the southeastern Michigan area attracted new residents with jobs in everything from heavy industry to machine shops to transportation.

    Detroit has always had a substantial share of single-family houses compared to other industrial hubs, which relied more on high-density multifamily housing. While homeownership rates were generally high, opportunities were not evenly dispersed, as racial redlining led to largely segregated neighborhoods and lower homeownership rates among blacks and ethnic minorities. Although redlining was common in the first half of the 20th century in many large American cities, Michigan set itself apart.  Its Home Rule Act allowed a great deal of self-governance by small cities leading to the creation of dozens of very small towns, all with different public services and both subtle and overt discriminatory policies. The Home Rule Act also allowed large companies to heavily influence local taxation policy and effectively create low tax havens in small towns, thus starving the greater Detroit area of tax revenue.

    Detroit started facing significant troubles in the late 1960s, as the 1967 race riots led to significant white flight. The OPEC embargo in the early 1970’s increased oil prices and opened the door to more fuel-efficient foreign competitors in auto manufacturing. The city’s decline began with significant population loss due to both unemployment and migration to suburban areas, resulting in deterioration of inner-city housing stock and severe underfunding of public services such as police, fire protection and education.

    Long known for its grit and determination, Detroit started to come back in the 1990s and early 2000s as the auto industry recovered. However, much of that progress was lost during the Great Recession due to predatory lending and the second collapse of American automakers. Many large blocks of the inner city were left with only one or two houses standing, and arson for insurance money plagued the housing stock.

    However, Detroit’s revival in the past ten years proved even bigger than all of its setbacks. The Lions, Tigers, Red Wings, and Pistons now all have their venues within easy walking distance of the revitalized downtown business and entertainment district. The city built a new riverfront parkway and renovated parks. Downtown has incredible energy once again, with bustling businesses and residential towers going up, not to mention the burgeoning art scene popping up in multiple locations.

    Laura Grannemann, Executive Director, Rocket Community Fund & Gilbert Family Foundation, gave an overview of the organizations' endeavors in the community. As one of the nation’s largest mortgage lenders, their Detroit Home Repair Fund and Detroit Tax Relief Fund work to head off displacement through preventing tax foreclosure and eviction.

    Detroit still faces many challenges, particularly in those neighborhoods hit hardest by out-migration, foreclosures, and underinvestment in city services. Wealth and influence remain highly concentrated, and the Home Rule Act micro towns remain an impediment to healthy Detroit finances and provision of basic services. Despite this, we found encouraging pockets of home-grown revitalization. Jeanette Pierce, president of City Institute, showed us how hyper-local organizing is bringing growth and renewal without troublesome gentrification and displacement. We met leaders from organizations such as the Southwest Detroit Business Association, Capital Impact Partners, and Live6 Alliance that advocate for fair housing and community engagement. Keeping people in the neighborhoods that multiple generations have called home is a hallmark of these local initiatives. Tactical rezoning has helped overcome some of the obstacles to development presented by Detroit’s traditional focus on detached single-family housing.

    The team also met Ike Blessitt, who personifies Detroit’s gritty reputation. Ike grew up in Hamtramck, one of the Home Rule Act towns completely surrounded by Detroit. As a four-sport high school star athlete, Ike attracted the attention of Detroit Tigers scouts and eventually made it to the major leagues with the 1972 Tigers. Today, even as a 76-year-old double amputee, Ike has continued his 15 years of teaching individuals, aged 6 to 60, how to play baseball. Like the development efforts, Ike keeps it local to help inner-city kids by building a complete baseball training facility in his Detroit backyard. The Ike Blessitt Sports Academy attracts kids from throughout Detroit.

    We came away from Detroit with a real appreciation for the daily challenges its residents overcome through innovation and community organizing. The lively sports and entertainment district will surprise new visitors, but digging deeper into the neighborhoods will show that this renaissance is just getting started.

Blog - Archives

The S-Curve Archives

  • Andrew Davidson

    Thoughts

    Dear Friends,

    As Andrew Davidson & Co., Inc. (AD&Co) reaches its 30-year milestone, I reflect on two seemingly contradictory ideas:  Firms need experience to guide clients through difficult times but sometimes it is necessary to discard past practices to achieve breakthroughs. 

  • Connor Campbell

    Thoughts

    For many people, having accessible transportation (a car, for example) is necessary. Most U.S. people live in areas without adequate public transportation and require vehicles to access jobs, healthcare, and groceries.

  • Daniel Swanson

    Thoughts

    As interest rates rise and fewer loans with refinancing incentive remain, other factors are primed to play a larger role in determining prepayment speeds in the coming months (and perhaps years). Turnover, the rate at which people move, is the most cited of these factors.  In this blog post, we’ll consider two other potential drivers: curtailments, or partial prepayments, and mortgage payoffs that don’t involve taking out a new loan.

  • 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.