Underlying Index Performance: The price of IUSA.DU closely tracks the performance of its underlying index, the S&P 500. Therefore, the ETF price fluctuates based on the aggregate performance of the 500 largest publicly traded companies in the US.

Supply and Demand: Market forces of supply and demand for IUSA.DU shares influence its price. Higher demand relative to supply drives the price up, while increased supply versus demand causes it to decline.

Expense Ratio: While not a direct driver of daily price changes, the expense ratio (ongoing fees) impacts the long-term return and attractiveness of IUSA.DU compared to similar ETFs.

Currency Exchange Rates: As a fund potentially traded in a different currency than the underlying assets, exchange rate fluctuations between the trading currency and the US dollar can affect the ETF's price.

Investor Sentiment: Broad investor sentiment towards the US stock market influences demand for IUSA.DU. Positive sentiment leads to increased investment, driving prices up, and vice versa.