Underlying Asset Performance: The primary driver is the performance of the underlying assets that the ETF tracks. If the index or basket of assets the ETF replicates goes up, the ETF's price should also increase.

Supply and Demand: Market forces of supply and demand influence the ETF's price. High demand can drive prices up, while increased selling pressure can push prices down.

Net Asset Value (NAV): The NAV, representing the per-share value of the ETF's holdings, is a key reference point. The market price usually stays close to the NAV, but deviations can occur.

Expense Ratio: The expense ratio, the annual fee charged for managing the ETF, can affect its long-term performance and indirectly its price as it reduces returns.

Trading Volume & Liquidity: Higher trading volume and liquidity typically lead to tighter bid-ask spreads and potentially more efficient price discovery.

Market Sentiment: Overall investor sentiment, whether bullish or bearish, can influence the ETF's price alongside the broad market trends.