Underlying Asset Performance: 00664R.TW tracks a specific index. The price of the ETF is directly impacted by the performance of the assets (stocks, bonds, etc.) within that index. If the underlying assets increase in value, the ETF's price will generally increase, and vice versa.

Supply and Demand: General market forces of supply and demand influence the ETF's price. Higher demand than supply will drive the price up, while higher supply than demand will lower it.

Net Asset Value (NAV): The NAV represents the per-share value of the ETF's underlying assets. While the market price can deviate slightly, it tends to track the NAV closely. Significant deviations can create arbitrage opportunities.

Investor Sentiment: Overall investor sentiment towards the asset class or market that the ETF represents can influence its price. Positive sentiment can lead to increased buying pressure and higher prices.

Market Conditions: Broader market trends, economic news, and global events can all indirectly affect the ETF's price by impacting the value of its underlying assets and overall investor sentiment.

Currency Exchange Rates: If the ETF holds assets denominated in a foreign currency, fluctuations in exchange rates can affect the ETF's price when converted back to the local currency.