Underlying Asset Performance: LWCE.PA tracks the MSCI Europe Communication Services index. The price of the ETF heavily depends on the combined performance of the constituent companies within that index. If these companies perform well (increased profits, positive news, etc.), the ETF price generally rises and vice-versa. Supply and Demand: Basic market forces of supply and demand also impact the price. Higher demand pushes the price upward, while increased selling pressure lowers it. Investor sentiment, macroeconomic conditions, and overall market trends all influence supply and demand. Expense Ratio & Tracking Error: The expense ratio, the annual fee for managing the fund, indirectly affects the return investors receive, and perceived tracking error (how closely the ETF follows its index) can impact its attractiveness and thus its price. Currency Exchange Rates: Since the ETF invests in European companies, currency fluctuations between the Euro and the trading currency (likely EUR) will affect returns for investors holding the ETF. Euro strength vs other currencies benefits holders, Euro weakness harms.