Recently, there has been a claim circulating online that the US stock market evaporated approximately $800 billion in market value at the moment of opening. However, this figure has not been confirmed by any authoritative institutions or official sources. In fact, at the opening time of 9:30 AM (Eastern Time), there is a significant technical and time delay in the real-time calculation of total market capitalization changes.
According to S&P Dow Jones Indices, the total market capitalization of the S&P 500 index is dynamically calculated based on the opening prices of constituent stocks and the number of shares outstanding. Initial data is merely a preliminary estimate and may be significantly revised later due to delayed openings, adjustments in company equity, or intraday reversals.
It is important to note that the fluctuations in index points do not equate to actual changes in market capitalization. To estimate market value changes, one must use the previous day's closing total market capitalization as a baseline and multiply it by the percentage change at the opening. For example, if the S&P 500 opens down 1.5% and its total market capitalization the previous day was $45 trillion, the theoretical loss would be approximately $675 billion. However, this figure still needs to be cross-verified with the total market index (such as the Wilshire 5000), as the S&P 500 only covers about 80% of the US stock market.
During the opening phase, due to lower liquidity, the concentrated release of overnight news, and order imbalances, there can be significant price volatility. Federal Reserve Chairman Jerome Powell recently pointed out that current stock valuations are “quite high,” and the market is highly sensitive to interest rate policies, further amplifying early morning emotional fluctuations.
Additionally, as a reference indicator of risk sentiment, Bitcoin's price at the time of writing is $68,273, with overall market sentiment leaning towards pessimism, reflecting investors' cautious attitude towards the macroeconomic outlook. However, it should be clear that the performance of crypto assets does not have a direct causal relationship with the fluctuations at the US stock market open; it only serves as an auxiliary observation value.
In conclusion, the so-called 'evaporation of $800 billion' is more likely an exaggerated expression driven by market sentiment rather than an accurate statistical result. Investors should focus on trend data rather than the volatility figures at a single point in time.