IG Credit Spreads Extremely Compressed, HY Divergence Intensifies

Overview

Goldman Sachs' latest 'Global Credit Trader' report focuses on an underappreciated phenomenon in the corporate credit market: while index-level spread valuations are in historically tight ranges, there is a significant divergence in the trend of spread dispersion beneath the surface across different markets. Using various spread metrics (bond-level, rating-level, sector-level), the report finds that spread dispersion in the Investment Grade (IG) market is unusually low, whereas dispersion in the High Yield (HY) market is very high. This difference has important implications for investment strategy: in the IG market, the potential for bottom-up selection is limited, with greater focus needed on market risk exposure and duration allocation; in the HY market, credit selection at the single-name level will be key to investment returns.

Core views

**IG and HY Spread Dispersion Present a 'Two Markets' Landscape** The core finding of the report is a historic divergence in the trend of spread dispersion between IG and HY bond markets. In the IG market, whether denominated in USD or EUR, spread dispersion is at its lowest levels in nearly a decade. Specifically, the bond-level spread dispersion metric for USD IG bonds (defined as the interquartile range standardized by the median, i.e., (P75-P25)/P50) is 0.56, sitting at the 15th percentile since 2016; for EUR IG, it is 0.51, at the 27th percentile. In stark contrast, spread dispersion in the HY market is at historical highs. The bond-level spread dispersion for EUR HY is 1.05 (97th percentile), and for USD HY, it is 0.77 (80th percentile). **Three Key Drivers Behind the Divergence** The report attributes this divergence to three key drivers. First, the rise in risk-free rates has generated significant yield-based demand, which is particularly strong in the IG market because yield-seeking investors such as pension funds and insurance companies favor IG-rated assets. When marginal buyers become less sensitive to differences in individual bond spreads and more focused on absolute yields, market pricing naturally leads to compressed spread dispersion. Data shows that from 2010 to 2021, USD IG spreads accounted for 43% of total yield, whereas today they account for only 14%; for USD HY, this ratio dropped from 73% to 37%, indicating that the contribution of spreads to relative value calculations is far smaller in the IG market than in HY. Second, HY companies are more sensitive to the current macro environment characterized by below-trend growth, high inflation, and tight monetary policy. Their financial cushions are thinner, making them more vulnerable to cost pressures from tariffs and commodity market disruptions, which are more likely to manifest in the HY market. Third, improved market liquidity has made a secondary contribution to the narrowing of spread dispersion in the IG market. The report shows that bid-ask spreads per unit of volatility have improved significantly over time in both markets, but USD IG has outperformed USD HY in both level and trend, thereby compressing the liquidity premium embedded in spreads and helping to narrow the distribution of spreads. **AI Financing Becomes a New Driver of Divergence** The report specifically notes that the ongoing wave of AI-related financing is becoming an increasingly important performance driver in the corporate bond market and has already driven spread dispersion at the rating level. Given that AI infrastructure construction will continue for years, the report expects this to lead to a persistent pattern of divergence, as evidenced by the accelerated debt issuance by hyperscalers in the AA-rated market. **Investment Strategy: Different Responses for Two Markets** Given the characteristic of low dispersion in the IG market, the report argues that bottom-up credit selection is unlikely to generate significant alpha, and quality and duration exposure are more effective. In USD IG, the report recommends continuing to optimize carry, preferring BBB ratings over higher-rated categories; in EUR IG, due to limited spread premium for BBB ratings and a more challenging European macro backdrop, it prefers A ratings over BBB. Given the characteristic of high dispersion in the HY market, credit selection at the single-name level is expected to be a key driver of investment returns. In USD HY, the report prefers to overweight BB, remain neutral on CCC, and underweight B, reflecting limited spread compensation for B ratings and an expectation that default rates may decline slightly in the coming months, while CCC still offers reasonable spread premiums. In EUR HY, the report takes a more cautious stance, overweighting BB, remaining neutral on B, and underweighting CCC, as it expects default rates to rise further.

Analysis framework

The report employs a bottom-up analytical framework combined with multi-dimensional measurements to characterize market structure. **Methodology for Quantifying Spread Dispersion**: The report first defines the broadest bond-level spread dispersion metric, namely the interquartile range of bond spreads standardized by the median (P75-P25)/P50. It then drills down into rating categories (e.g., AAA/AA, A, BBB within IG; BB, B, CCC within HY), as well as between and within sectors, to comprehensively measure dispersion across different dimensions. This approach allows readers to clearly see that spread dispersion is not evenly distributed but is more pronounced in the highest-rated (AAA/AA) and lowest-rated (CCC/B) segments. **Multi-Dimensional Cross-Validation**: By comparing the percentile rankings of different metrics (e.g., P90/P10 vs. P75/P25), the report confirms the consistency and robustness of the pattern of compressed IG dispersion and intensified HY dispersion, which holds roughly even under the broadest measurement criteria. **Attribution of Drivers**: The report categorizes the reasons for the divergence in dispersion into three layers: demand technicals (yield-driven), fundamentals (differential impact of the growth-inflation-policy mix on companies of different ratings), and market microstructure (liquidity improvement). This attribution framework helps readers understand why IG and HY are moving in opposite directions, rather than simply attributing it to market sentiment.

Methodology notes

• Industry/Sector Analysis Framework

  Spread Dispersion

  This report uses the (P75-P25)/P50 metric to measure the degree of dispersion in spread distributions among bonds, ratings, and sectors. Simply put, a larger value indicates greater differences in credit spreads between bonds, meaning the market prices good and bad companies more distinctly; a smaller value indicates that credit spreads are similar across the board, making it difficult for market pricing to distinguish quality. The report uses this metric to reveal the fundamental structural differences between the IG and HY markets.

• Industry/Sector Analysis FrameworkSupply and Demand Framework

  Yield-Based Demand Technical

  When risk-free rates rise, yield-seeking investors (such as pension funds and insurance companies) place greater emphasis on the absolute yield of bonds rather than minor differences in credit spreads. They tend to buy IG bonds to lock in higher yields, which flattens and compresses the spreads of different bonds in the IG market (the premium portion relative to risk-free rates). The report uses this principle to explain why spread dispersion in the IG market is so low: because major buyers are no longer picky about credit differences among individual bonds.

• Company Fundamentals and Financial FrameworkOperating/Financial Leverage Analysis

  Financial Cushions / Growth Sensitivity

  The report argues that HY companies have thinner financial cushions (e.g., weak cash flows, high debt), making them more susceptible to shocks in an environment of below-trend economic growth, elevated inflation, and less accommodative monetary policy. This leads to greater disparities in operating performance and credit conditions among different HY companies, thereby driving up spread dispersion. This is a typical analytical logic where 'differences in financial fundamentals drive pricing divergence.'

• Industry/Sector Analysis FrameworkSubstitution Effect Analysis

  Second-Order Driver of Liquidity

  The report points out that improved liquidity in the IG market (narrowing bid-ask spreads) reduces the additional compensation (liquidity premium) required by investors for holding illiquid bonds, which helps narrow the spread distribution among IG bonds, thereby reducing spread dispersion. This represents a transmission logic of 'improved market microstructure → enhanced pricing efficiency → reduced differentiation,' serving as a secondary but non-negligible driver.

Key data

• USD IG Bond Spread Dispersion (P75-P25)/P500.5610-year historical median is 0.69, currently at the 15th percentile since 2016 (low)
• EUR IG Bond Spread Dispersion (P75-P25)/P500.5110-year historical median is 0.6, currently at the 27th percentile since 2016 (low)
• USD HY Bond Spread Dispersion (P75-P25)/P500.7710-year historical median is 0.69, currently at the 80th percentile since 2016 (high)
• EUR HY Bond Spread Dispersion (P75-P25)/P501.0510-year historical median is 0.78, currently at the 97th percentile since 2016 (historically extremely high)
• Share of Total Yield Attributable to USD IG Spreads (2010-2021)43%This ratio has now fallen to 14%
• Share of Total Yield Attributable to USD HY Spreads (2010-2021)73%This ratio has now fallen to 37%

Impact & implications

The report believes that the divergent spread dispersion landscape between IG and HY will persist as long as yields remain elevated (consistent with Goldman Sachs economists' and rate strategists' baseline forecasts for the next year). **Specific Implications for Investors**: - **IG Market**: Low dispersion limits the scope for selection strategies to create alpha. Investors should devote more effort to market risk exposure and duration allocation. - **HY Market**: High dispersion means selection strategies are crucial, especially when avoiding potential asymmetric downside risks. - **Sector Level**: The wave of AI-related financing will continue to be a significant performance driver for certain sectors and issuers, leading to persistent divergence at the rating level. - **USD Market**: With a more favorable combination of growth, inflation, and monetary policy compared to the Eurozone, Goldman Sachs is overweight USD credit bonds and underweight EUR credit bonds; within the USD market, it slightly prefers IG over HY.

Risks

• Unexpected shifts in the Fed/ECB policy path (e.g., more hawkish/dovish) could alter interest rate trends, thereby affecting yield-based demand
• An unexpected downturn in economic growth could impose greater financial pressure on HY companies, leading to rising default rates
• If the AI investment boom falls short of expectations or encounters significant technological setbacks, it could bring credit risks to related issuers
• Geopolitical risks could lead to new disruptions in energy prices or supply chains, affecting specific sectors (e.g., retailers, airlines)

What to watch

• Changes in yield levels: This is the core condition for whether the divergent dispersion pattern between IG and HY can persist
• Subsequent developments in AI-related financing and their actual impact on corporate credit quality
• Evolution of the Eurozone macro environment, particularly its impact on the trajectory of HY default rates
• Whether inter-sector dispersion in the IG market will expand from its current low base