The S&P 500 tumbled into dreaded bear market territory on Monday

President Donald Trump announced his tariffs on Wednesday.

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• The S&P 500 briefly entered bear market territory on Monday, down 20% from recent highs.
• Stocks have cratered since Wednesday's tariff announcement, with the selling continuing on Monday.
• The Nasdaq-100 ended Friday's session in a bear market.

The S&P 500 briefly entered bear market territory on Monday amid the Trump tariff chaos.

A bear market is defined...