For 15 months, the stock market has moved less on economic data or Federal Reserve policy than on posts from one source: President Donald Trump. Traders now find themselves constantly monitoring his communications for signals that could send markets swinging in either direction.

The dynamic marks a fundamental shift from traditional market drivers. Rather than parsing unemployment figures or corporate earnings, investors increasingly base positioning on the president's social media activity and public statements. This creates a uniquely unpredictable environment where policy direction can shift via a single post.

Market participants describe the situation as unprecedented. When a single individual's communications can override standard financial analysis, conventional risk management becomes more difficult. Portfolio managers must now factor in political communication analysis alongside traditional metrics like valuations and earnings.