As a broad measure of the US economy, the GDP report directly impacts investor sentiment and can cause short-term market volatility. Given that SPY tracks the S&P 500, which includes companies across all sectors of the US economy, any significant deviation from expected economic performance metrics like GDP can lead to immediate but generally temporary shifts in the ETF's price. The slight miss in GDP growth expectations suggests a potential for short-term volatility, but the close alignment with estimates may mitigate extreme market reactions.