Underlying Index Performance: SPUS mirrors the S&P 500 index. The ETF's price will fluctuate based on the index's movements.

Supply and Demand: High demand for SPUS shares can push the price up, while increased selling pressure can lower it.

Market Sentiment: Overall investor optimism or pessimism can influence the trading activity and price of SPUS.

Expense Ratio: While not a direct price driver, SPUS's expense ratio impacts the overall return for investors.

Trading Activity: Large trading volumes in SPUS can create volatility and price swings.

Economic Indicators: Economic data releases such as inflation, GDP, and employment figures can affect market sentiment and the S&P 500, subsequently impacting SPUS.

Interest Rates: Changes in interest rates set by the Federal Reserve can influence the attractiveness of stocks and affect the S&P 500.

Geopolitical Events: Global political events, trade disputes, and international relations can create uncertainty and impact market performance.

Company Specific News: Significant news or events related to the companies included in the S&P 500 index can impact the index and SPUS.