Stocks Week Ahead: Rising Credit Spread Risks Put Volatility Floors to the Test

Published 29/09/2025, 04:39
Updated 29/09/2025, 08:04

An interesting development occurred on Friday that bears are watching this week: the NYSE McClellan Summation Index fell below 500. From what I can tell, this is the first time the index has dropped below that level since May.NYSI-Chart

A drop below 500 doesn’t necessarily mark the end of the rally, but it does suggest the market’s advance may be running out of steam. If the Summation Index continues to weaken from here, it would signal that the odds of the rally continuing are fading. This will be something to watch as the week progresses, especially if breadth metrics remain weak.

Examining the chart, the Summation Index appears to resemble a head-and-shoulders pattern, with the index currently positioned directly on the neckline.

Friday, however, was a strange day of trading. The S&P 500 was up 55 bps, yet volatility, correlations, and the dispersion indexes all fell—an unusual combination. The one notable exception was that both 9- and 21-day realized volatility actually rose. It’s a good reminder that when realized volatility is this low, even a slight move in the S&P 500 can push realized volatility higher, which likely means implied volatility is near a floor.SPX Volatility

Another thing worth pointing out is that spreads in Europe have started to widen. The Italian 10-Year minus the German 10-year has risen to 87 bps, which is still historically very tight but wider over the past few days. I’m not sure if the rules of the RSI apply to these types of sovereign spreads, but it has clearly formed a bullish divergence.IT10Y-DE10Y Chart

We have recently seen similar developments with the 10-year euro swap spread as well.EUR Swap vs 6 M Chart

We care about spreads in Europe because high-yield credit spreads in the US tend to trade right along with changes in credit spreads in Europe. So if those spreads start to widen, there’s a good chance the spreads here in the US will begin to widen as well.IT10Y-DE10Y-Daily Chart

Some may find it surprising to see that HY spreads can trade right along with implied volatility levels for stocks.BAMLH0A0HYM2 Chart

Overall, with volatility this low and spreads this tight, it highlights the complacency and risks across not just the stock market but also the bond market. In some ways, it makes sense that spreads have tightened in Europe, given the shifting political landscapes in Germany and France, as well as the rising debt loads.

However, that doesn’t mean it makes sense for US high-yield debt to trade this tight to Treasuries. It seems possible, and even likely, that US credit spreads are picking up a false signal from Europe—failing to recognize that the tighter spreads there reflect increasing risks, not greater risk-taking.

Original Post

Latest comments

Risk Disclosure: Trading in financial instruments and/or cryptocurrencies involves high risks including the risk of losing some, or all, of your investment amount, and may not be suitable for all investors. Prices of cryptocurrencies are extremely volatile and may be affected by external factors such as financial, regulatory or political events. Trading on margin increases the financial risks.
Before deciding to trade in financial instrument or cryptocurrencies you should be fully informed of the risks and costs associated with trading the financial markets, carefully consider your investment objectives, level of experience, and risk appetite, and seek professional advice where needed.
Fusion Media would like to remind you that the data contained in this website is not necessarily real-time nor accurate. The data and prices on the website are not necessarily provided by any market or exchange, but may be provided by market makers, and so prices may not be accurate and may differ from the actual price at any given market, meaning prices are indicative and not appropriate for trading purposes. Fusion Media and any provider of the data contained in this website will not accept liability for any loss or damage as a result of your trading, or your reliance on the information contained within this website.
It is prohibited to use, store, reproduce, display, modify, transmit or distribute the data contained in this website without the explicit prior written permission of Fusion Media and/or the data provider. All intellectual property rights are reserved by the providers and/or the exchange providing the data contained in this website.
Fusion Media may be compensated by the advertisers that appear on the website, based on your interaction with the advertisements or advertisers
© 2007-2025 - Fusion Media Limited. All Rights Reserved.