NEW YORK — The Japanese yen strengthened 2.3 percent against the U.S. dollar this week, its largest weekly gain since coordinated U.S.-Japan intervention in late July, as rate hike expectations dismantle years of accumulated carry-trade positioning.
The move reverses a brutal six-week decline that sent the yen to a four-decade low. Market consensus now prices a 25 basis point Bank of Japan rate hike in September as highly probable, with some traders gaming a more aggressive 50 basis point move. That risk premium has compressed carry-trade positioning that had grown dangerously extended.
Data from Citigroup shows yen positioning flipped from bearish to bullish since early August. Interbank flows confirm the move is real: leveraged funds, banks and real-money investors have been net buyers of yen throughout the week.
"Investors are now increasingly hesitant to aggressively short the JPY, especially with a BOJ rate hike in September adding risk to such trades," said Rong Ren Goh, fixed income portfolio manager at Eastspring Investments.
The carry unwind carries systemic risk. Stephen Jen, CEO and co-CIO of Eurizon SLJ Asset Management, warned that when a currency reaches extreme undervaluation with extended positioning, the deleveraging can force rapid, destabilizing moves. He drew a parallel to Long-Term Capital Management's 1998 collapse, when forced unwinding triggered market contagion across asset classes.
The yen's depreciation accelerated this year as markets skeptical of Prime Minister Sanae Takaichi's stimulus plans paired with conviction that the BOJ was falling behind the policy curve. Tokyo conducted record solo interventions in April and May when the yen breached 160 per dollar. The critical inflection came in July and August, when Washington joined Tokyo in rare coordinated action after the yen hit 163.99—a level unseen since 1986.
