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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U.S. Mortgage High Yield Indexes From Andrew Davidson & Co Added to St. Louis Fed's FRED DatabaseNews
For several years, AD&Co has tracked the total rate of return (TRR) performance of the GSE CAS and STACR CRT in its U.S. Mortgage High-Yield Indices. The AD&Co Mid-Tier index constitutes a broad market measure of the TRR performance of GSE CRT. The related sub-indices segregate the CRT market into 4 index Tiers by attachment point, reflective of the credit exposure of the various classes of underlying CRT ranging from B to M1.
We are pleased to announce that the historical time series for these indices is now publicly available on the St. Louis Federal Reserve's FRED database, along with the credit-adjusted OAS (CrOAS) for each series. FRED is host to almost 800,000 data series from more than 100 sources. The indices published on FRED can be viewed here. Detailed performance analysis related to the index is available on a monthly basis at through AD&Co.
For more information please contact Rob Landauer at 212-274-9075, email Rob at rob@ad-co.com or visit www.ad-co.com.

Disclaimer: The AD&Co U.S. Mortgage High-Yield Index serves as an informational index and is not for commercial-use purposes. The Index’s accuracy, completeness, timeliness, and suitability for any purpose are not guaranteed. The Index does not constitute (1) investment, legal, accounting, tax, or other professional advice or (2) any recommendation or solicitation to purchase, hold, sell, or otherwise deal in any investment. This Index has been prepared for general informational purposes, without consideration of the circumstances or objectives of any particular investor. Any reliance on the Index is at the reader’s sole risk. All investment is subject to numerous risks, known and unknown. Past performance is no guarantee of future results. For investment advice, seek a qualified investment professional. Not for redistribution without permission. Note: An affiliate of Andrew Davidson & Co., Inc. engages in trading activities in investments that may be the same or similar to those featured in the Index.
The S-Curve Archives
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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.
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ThoughtsHow 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.
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ProductsThe 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:
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ThoughtsFHFA 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.
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ThoughtsIn 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.
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ThoughtsIn 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.
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ThoughtsIntroduction
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.
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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.
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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.
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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.