Underlying Asset Performance: SMAC11.SA's price is directly linked to the performance of the small-cap companies it tracks in Brazil. If those companies perform well, the ETF price generally rises. Conversely, poor performance leads to price declines.

Market Sentiment: Overall investor sentiment towards the Brazilian stock market and small-cap stocks specifically influences SMAC11.SA. Positive sentiment drives demand, increasing the price, while negative sentiment leads to selling pressure and lower prices.

Economic Conditions: Brazil's macroeconomic environment, including GDP growth, inflation, interest rates, and unemployment, impacts the profitability and valuation of small-cap companies, thus affecting SMAC11.SA.

Currency Fluctuations: The Brazilian Real's exchange rate against other currencies can influence the ETF's price, particularly if the underlying companies have significant international operations or debt denominated in foreign currencies.

ETF Supply and Demand: Like any traded asset, the forces of supply and demand affect SMAC11.SA's price. High demand relative to supply pushes the price up, while excess supply compared to demand brings the price down.