World’s Most Pressured Bonds Face a Traditionally Terrible Month

Longer-maturity government bonds (over 10 years) historically face a challenging September, having posted a median global loss of 2% during that month over the past decade, making it their worst monthly performance of the year according to Bloomberg data.

Analysis

Historical data indicates a significant seasonal headwind for global long-maturity government bonds as September approaches. Analysis of performance over the last decade, compiled by Bloomberg, reveals that bonds with maturities exceeding 10 years have consistently experienced their worst monthly results in September. Specifically, this asset class has posted a median loss of 2% during the month, a data point that underscores the historically treacherous nature of this period for long-duration sovereign debt. This well-defined negative seasonality presents a notable risk factor for portfolios with substantial exposure to this segment of the fixed-income market.

Key Decisions for Investors

• Investors with long positions in government bonds with maturities over 10 years should review their exposure and consider tactical reductions or hedging strategies to mitigate potential losses from this strong negative seasonal trend.
• It may be prudent for those considering new allocations to long-duration sovereign debt to delay entry until after this historically weak month concludes.
• Traders could view this recurring pattern as a potential opportunity for tactical short positions in long-dated government bond futures or related instruments, anticipating a repeat of the historical 2% median loss.