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.
-
Impressions from SFVegas and OB Summit 2026EventsAD&Co recently sponsored and attended SFVegas 2026 and Optimal Blue Summit 2026. This post shares the AD&Co team's unique perspectives and key takeaways from attending both conferences.
The New Non-Agency Model, Real Estate Exposure to Climate-Related Hazards & Escrow Analysis (Eknath Belbase)
Daniel and I recorded a Exchange Live: Tech Odyssey podcast on Kinetics and the upcoming release of LDM v4.0. The 30-minute audio and accompanying slides are available on demand. We focused on DSCR/prepay penalty, along with the addition of climate.
My panel on climate risk and property values went well – this year the focus shifted a bit to resilience, and the opportunity to reduce the rate of insurance increases by putting money up front into strengthening homes. Several states are funding the initial outlay required in pilot programs as part of insurance affordability initiatives (including Deep South states). David Zhang of MSCI started off the discussion with a tally of damages from physical risk sorted into quintiles of cost (measured against home value). The top quintile is already at a mean of 55bps per year of loss (these are only losses from weather events of scale and insurance needs to include costs such as fires starting from appliances or flooding from sewer back-ups).
Finally, we learned that Cotality has a database of property tax histories on all U.S. single-family homes and is working on an approach to forecast taxes going forward, so our vision of a full escrow-conditioned HPA and LDM is within reach.
Contact us for more information on LDM v4.0.
Key Takeaways (Daniel Swanson)
It was great to see so many familiar faces and to see the conference booming (though also a bit foreboding – the last time it was so packed, there was a crisis shortly thereafter). Here are a few key takeaways I had from talking to different people.
Non-QM
- There is a lot of interest in non-QM from many sophisticated participants
- Analyzing new loans is complicated and most people are not taking advantage of all the information in the deals
Climate
- State-level behavior is changing, particularly FL payups, perhaps due to taxes and insurance (that link is hard to prove)
- Servicers are starting to care about T+I for several different reasons (escrow float=positive, delinquency risk=negative)
Credit Scores
- Participants are mostly worried about disruption to their process when thinking about credit scores rather than performance
AI
- Everyone is thinking about AI, whether they are talking about it or not (and there are plenty of people talking about it)
How AD&Co and Optimal Blue Are Transforming Pipeline Risk Management for Loan Originators (Yvonne Chen)
At the Optimal Blue Summit 2026, we connected with loan originators and our alliance partners at Optimal Blue to discuss the evolving challenges in the mortgage origination sector. The conversations and conference sessions reinforced the patterns we've been seeing: Origination is a thin margin business, and originators must carefully manage the uncertainty and financial risks from locking rates at the beginning of the application process through to loan sale. Lenders manage their pipelines across agency and non-agency loan products while simultaneously borrowing closing funds and hedging to protect their profit margins – all while contending with interest rate volatility, fallout risk, basis risk in non-QM products, and borrower renegotiation. Fallout rates have climbed in recent years as borrower behavior shifts and competition intensifies in a low-volume market, making accurate pipeline risk management more critical than ever. Optimal Blue and AD&Co see the persistent need for the kind of sophisticated analytics that we can provide to help lenders stay ahead of these challenges.
AD&Co was featured on a panel where Matteo Caracciolo-King had the chance to present a first look at our insights on consumer behavior in the application process based on Optimal Blue’s national application data set. Originators were keenly interested in forecasting application stage transition probabilities, which vary over time and across interest rates, as well as the kind of financial risk metrics that AD&Co can provide. The conference confirmed our view that, as pipeline hedging grows more complex, particularly with a fast-growing non-agency market, we see a meaningful opportunity to help originators strengthen their risk management through advanced analytics integrated into the Optimal Blue platform they already rely on.
The S-Curve Archives
-
ThoughtsRecently, aggregators have crossed market borders by issuing residential mortgage-backed securities (RMBS) backed by owner-occupied (OO), GSE-eligible conforming loans. Additionally, conforming mortgage loans have drawn investment interest from insurance companies fronted by aggregators and evaluated by third-party firms. These developments constitute historically rare disintermediations of the nearly monopsonist purchases of conforming loans by the GSEs.
-
PodcastJoin Rob Landauer in a conversation with Abe Martin as they discuss his recent Pipeline article, "Modeling the Balance Behavior of HELOC Borrowers." In this episode, they highlight key points from the article as he shares insights into the draw component of HELOCs and provide an update on the beta rele
-
News
We’re excited to announce a major addition to the Andrew Davidson & Co., Inc. (AD&Co) team. Industry leaders Kelli Sayres and Gene Park, known for building and scaling leading fixed-income analytics platforms, have joined AD&Co’s Business Development team.
-
ThoughtsBuilding on our earlier research on expanded consumer attributes, AD&Co continues to explore how credit data contributes to modeling delinquency and prepayment risk, which are key drivers of mortgage servicing rights cash flows and valuation.
-
EventsAndrew Davidson recently joined NFM Lending’s Greg Sher on the One On One podcast to discuss our recent white paper, “The Impact of Moving Away From the Tri-Merge Standard.”
-
EventsAD&Co recently sponsored and attended SFVegas 2026 and Optimal Blue Summit 2026. This post shares the AD&Co team's unique perspectives and key takeaways from attending both conferences.
-
NewsAD&Co US Mortgage High Yield Indices
The Federal Reserve Economic Data (FRED) portal, housed by the Federal Reserve Bank of St. Louis, has been publishing AD&Co’s CRT indices since 2019. These series posted under the overall name of “US Mortgage High-Yield” include total return rates and credit and option-adjusted spreads (crOAS) – a projected return’s spread over Treasury (in the past, Libor). These series are available going back to 2014-end and tiered by CRT initial supports.
-
ThoughtsIn July 2025, the US Federal Housing Finance Agency (FHFA) announced that the government-sponsored entities (the Enterprises or GSEs), Fannie Mae and Freddie Mac, would permit lenders to choose between Classic FICO and VantageScore 4.0 credit score models for loans sold to the GSEs. FHFA also stated in a social media post that the tri-merge standard would be maintained for mortgage underwriting. Nevertheless, some mortgage industry stakeholders recommend moving away from the tri-merge standard for GSE mortgages in favor of a single or bi-merge report standard.
-
News
As housing faces more climate threats that result in more losses, the insurance program that it sits on is teetering on the brink of collapse. Yet, the home insurance market has three distinct stakeholders that have competing priorities, and today, there is no motivation for a collaborative solution.
Understanding how to strengthen and protect the current structure requires looking at the cost burdens along with the risk for each of those parties.
-
ThoughtsThere has been a flurry of activity in the mortgage markets since the 2018 passage of the Economic Growth, Regulatory Relief, and Consumer Protection Act. This act requires the Federal Housing Finance Agency (FHFA, now known as US Federal Housing) to validate and modernize the credit score models used in the housing finance system. It should be noted that so far, the discourse has been around mortgages sold to the Enterprises (Fannie Mae and Freddie Mac). Ginnie Mae has not provided any guidance on their plans to start using new credit score models.