Stock market reaches new highs under Trump administration in 2026

The U.S. stock market has risen sharply since Donald Trump won the 2024 election. The S&P 500 index gained 36% between November 2024 and September 2026. It rose nearly 18% in 2025 alone.

Some analysts are now asking whether the market has risen too far. One warning sign is the Shiller P/E ratio, which measures how expensive stocks are compared to company earnings. It has gone above 30, a level seen only six times in the past 156 years. Five of those times, a major market fall followed.

Borrowing to buy stocks also reached a record high of over $1.5 trillion earlier in 2026. Analysts have pointed to tariff changes, geopolitical conflict, and rising government debt as possible risks to the market.