Shifting Dynamics: Weakening Yen-Stock Correlation Challenges Conventional Wisdom in Japanese Markets

In the ever-evolving landscape of the Japanese market, the once steadfast belief that a cheaper yen inherently benefits exporters and propels share prices is facing a paradigm shift.

Contrary to traditional wisdom, the yen's exchange rate now exerts diminishing influence on Japanese stocks. Since July, the correlation between the Topix index and the dollar/yen rate has registered at a mere 0.23—a statistical weakness. Furthermore, the link between the yen and the Nikkei 225 during the same period has taken an unexpected turn, displaying a slightly negative correlation.

The waning connection between the yen and share prices can be attributed to the transformation of Japanese exporters. Esteemed companies like Sony Group Corp. and Hitachi Ltd. have long departed from their previous models of exporting domestically manufactured goods, opting for a more global and diversified approach.

Seiya Nakajima, visiting professor of international finance at Fukui Prefectural University, remarks, "Some people say a cheap yen will benefit exporters, but the impact of that is very limited after the hollowing-out of the domestic manufacturing base."

The data suggests that the Topix index's apparent correlation with the yen was notable only in the first half of 2023, as indicated by the orange dots. Yet, this connection appears tenuous, with other factors such as Warren Buffett's investments in trading firms and optimism surrounding corporate governance improvements driving Japanese shares during that period.

Highlighting this point, the impact of a cheaper yen on companies like Hitachi and Sony is limited. For instance, Hitachi's earnings before interest, taxes, and amortization increased by a mere ¥200 million ($1.3 million) for each one yen depreciation against the dollar. The overall sentiment is that for many chip-related companies, global economic outlook and sectoral dynamics carry greater weight than foreign-exchange rates.

The correlation between the dollar/yen rate and the Topix Electronics Appliance index, constituting 17% of the stock market, has decreased since the pandemic. This shift underscores that, for numerous industries, factors beyond the yen are increasingly influencing market dynamics.

While a cheaper yen still yields currency translation gains for Japanese companies with significant overseas sales, the automotive sector remains an exception. Automaker shares maintain a strong correlation with the yen, driven by their substantial vehicle exports. However, this linkage weakened in 2022 due to chip shortages affecting production, only to resurface last year.

Nevertheless, automakers represent only 9% of the Topix, challenging the prevailing perception that Japan's economy is solely export-driven. The reality check reveals that Japan's exports have stagnated over the past decade, partly due to production shifts abroad and a loss of competitiveness. It's evident that investors are no longer drawn to Japanese stocks solely based on the premise of a cheap yen.

In conclusion, the evolving dynamics in the Japanese market underscore the need to reassess long-standing assumptions about the yen's impact on share prices, as the landscape continues to shift in response to global economic forces and corporate strategies.