Index Performance: FFIU.US tracks the Fidelity U.S. Quality Factor ETF, so its price is heavily influenced by the performance of the underlying index. A rising index typically pushes FFIU.US higher.

Investor Demand: Increased buying pressure drives the price up, while higher selling pressure decreases it. Supply and demand are always key.

Market Sentiment: General optimism or pessimism in the stock market can spill over into ETFs like FFIU.US, affecting trading volume and price.

Fund Flows: Inflows into FFIU.US can increase demand, potentially pushing the price up, while outflows can have the opposite effect.

Expense Ratio: Although a small factor, the expense ratio can impact returns over time, subtly affecting the long-term perceived value and price.

Underlying Holdings: The performance of the specific companies and assets held by FFIU.US within the quality factor index directly impacts the ETF's price.