Underlying Asset Performance: The primary driver is the performance of the assets the ETF tracks. If those assets rise, the ETF price tends to increase; if they fall, the ETF price tends to decrease.

Supply and Demand: Increased demand generally drives the price up, while increased selling pressure (supply) can push the price down. ETF creation/redemption mechanisms also impact supply.

Market Sentiment: Overall market mood and investor confidence influence buying/selling decisions affecting price. Positive sentiment can lead to increased buying, negative to selling.

Expense Ratio: While not directly impacting daily price fluctuations, a higher expense ratio can slightly reduce long-term returns compared to similar ETFs with lower costs.

Currency Fluctuations: If the ETF holds assets denominated in a foreign currency, exchange rate changes can affect the ETF's price in your local currency.

Index Tracking Error: How well the ETF mirrors its benchmark index's performance influences price accuracy. Larger tracking error can lead to deviations.

Interest Rates: Changes in interest rates can impact the valuation of certain assets held within the ETF, such as bonds or dividend-paying stocks.

Economic Conditions: Broad economic factors like GDP growth, inflation, and unemployment can indirectly impact the underlying assets and therefore the ETF's price.

Political Events: Major political events, policy changes, and geopolitical risks can create market volatility, influencing investor sentiment and ETF prices.

Liquidity of Underlying Assets: If the assets held by the ETF are difficult to buy or sell quickly, it can affect the ETF's trading price and its ability to track its index.