Sovereign bond yields have been climbing throughout 2026, with the pace accelerating in recent weeks across developed markets. However, no single factor explains the sell-off. While inflation and debt levels are often cited, their relationship with yield increases is inconsistent. South Korea, with a modest debt-to-GDP ratio of 52 per cent, has seen yield jumps comparable to Italy, where public debt stands at 137 per cent of GDP. Similarly, Italy and Spain, both experiencing inflation above 4 per cent, have lagged behind France in yield increases despite France’s lower inflation rate of 3 per cent.
Economic growth also plays a role. The steady expansion of US real GDP helps account for larger yield rises there compared to Italy, which faces higher debt and inflation. Political risk remains an unpredictable driver. French bond yields have surged to levels reminiscent of the European debt crisis amid election uncertainty and a deteriorating fiscal outlook.
Japan stands out as the biggest outlier. The 10-year JGB yield has risen nearly one percentage point in 2026, matching moves in Gilts and Italian debt, even though Japanese inflation was only 1.9 per cent in August. Decades of deflation mean that these “normal” inflation levels, combined with a weak yen and energy shocks, are a significant economic jolt.
Author: Hakyung Kim, published October 3 2026.
Source: Financial Times Markets · Summarized by HeadlinesBriefing