Analysis of Market Impact from Strong U.S. Economic Data Driving Stock Market Gains and Yen Intervention Expectations

On December 23, 2025 (event date), the market focused on two core factors: strong U.S. economic data driving stock market gains, and foreign exchange market volatility triggered by expectations of Japanese yen intervention [0][1][5][6].

The U.S. Bureau of Economic Analysis (BEA) released the final third-quarter GDP value at 4.3%, far exceeding the market consensus of 3.2%-3.3%, and higher than the second quarter’s 3.8%, marking the highest growth rate in two years [1][2][3][4]. Core drivers include:

1. Consumer spending: Third-quarter growth of 3.5%, a significant increase from the second quarter’s 2.5%, covering both goods and services sectors, with a surge in electric vehicle purchases before the tax credit deadline on September 30 being a key driver [4].
2. Net exports: Declining imports (affected by tariff policies) and moderate export growth together narrowed the trade deficit, contributing significantly to GDP growth [3][4].

From December 22 to 23, 2025, Japanese Ministry of Finance officials repeatedly warned about “one-sided, sharp exchange rate fluctuations” and stated they are ready to take intervention measures [5][6][7]. Earlier, USD/JPY had hit a 10-month high of 157.89, then fell to around 155.80 after the warnings, a drop of 0.75% [6].

1. Policy and Market Transmission of Economic Data
   : The better-than-expected GDP growth data changed market expectations for Federal Reserve policy, with Treasury yields rising as investors re-evaluated the possibility of rate cuts in early 2026; meanwhile, tech stocks led U.S. stocks higher, with NVIDIA (NVDA) up 3% and Amazon (AMZN) up 1.6%, pushing the S&P 500 to a new all-time high [0][2].
2. Global Market Impact of Yen Intervention
   : Japanese export-oriented company stocks underperformed due to the stronger yen, while import-dependent industries rose slightly; investors increased demand for safe-haven assets like Japanese government bonds to avoid intervention risks [7].

:

• Economic data lag: Third-quarter GDP data was delayed due to a government shutdown and may include one-off factors (such as the electric vehicle purchase boom); subsequent revisions and fourth-quarter data need attention [8].
• Policy uncertainty: U.S. core PCE inflation rose to 2.9%, above the Federal Reserve’s 2% target, potentially delaying rate cuts [4]; Japan has not implemented actual intervention, so subsequent exchange rate volatility risks remain [5][7].

:

• U.S. economic resilience: Consumer spending (accounting for 70% of GDP) continues to grow, indicating a solid economic foundation [4].
• FX trading opportunities: The interplay between yen intervention expectations and Federal Reserve policy expectations provides potential opportunities for FX traders [5][6].

On December 23, 2025, the U.S. third-quarter GDP grew beyond expectations to 4.3%, mainly driven by consumer spending and net exports, pushing the three major U.S. stock indices higher [0][1][2][3][4]; Japanese Ministry of Finance officials issued foreign exchange intervention warnings, leading to a drop in USD/JPY [5][6][7]. The market needs to focus on subsequent economic data revisions, Federal Reserve policy changes, and whether Japan implements actual intervention.