There isn't a hard-and-fast definition of exactly what constitutes a stock market crash. For example, the S&P 500 went into a bear market in 2022, falling as much as 25% below its previous peak. However, many observers didn't call this decline a crash because it happened over several months.

Stocks have rallied hard for most of this week, as investors have grown less pessimistic about both President Trump's tariff war and the risks to central-bank independence. Here is a breakdown of how the market has bounced since Monday.