Underlying Asset Performance: The price of USSX.TO, an ETF tracking US stocks, heavily relies on the performance of its holdings.

Currency Fluctuations: Since USSX.TO likely holds US dollar-denominated assets, changes in the CAD/USD exchange rate impact its CAD price.

Supply and Demand: Increased investor demand pushes the price up, while increased selling pressure lowers it.

Market Sentiment: Overall market optimism or pessimism towards US equities influences investor interest in USSX.TO.

Interest Rates: US interest rate policies can affect the attractiveness of US stocks and, consequently, USSX.TO.

Economic Data: US economic indicators like GDP growth, inflation, and employment figures influence investor confidence.

ETF Management Fees: The fund's expense ratio slightly reduces the overall return and affects its trading price indirectly.

Global Events: Geopolitical events, trade wars, or global economic downturns can impact US stocks and USSX.TO's value.

Sector Performance: If USSX.TO is heavily weighted towards a specific sector, the performance of that sector is key.

Index Tracking Accuracy: How closely the ETF replicates its underlying index affects its price relative to the index.