The VIX, Wall Street's 'fear gauge,' reaches its highest level since the 2020 pandemic market plunge.

• The VIX reached its highest level on April 2, 2024, following the Federal Reserve's emergency measures during the Covid 19 pandemic, as per FactSet.
• In March 2020, the VIX reached a peak of 85.47, as reported by FactSet.
• The VIX is determined by the cost of options on the S&P 500.

On Monday morning, the expected volatility in the stock market increased to its highest level in over four years, coinciding with a sharp decline in global equities.

On Monday, the VIX surpassed 50, marking a significant increase from its value of approximately 23 on Friday and 17 a week prior.

Since its intraday high of 57.24 on April 2, 2024, following the Federal Reserve's emergency actions during the Covid 19 pandemic, the VIX has not been higher. On March 20, 2020, the VIX reached a peak of 85.47, according to FactSet.

The VIX measures expected volatility on the S&P 500 over the next 30 days and is commonly known as Wall Street's "fear gauge."

The VIX has been trading below 20 since the Covid sell-off subsided.

Although VIX spikes often occur during market sell-offs, they can also be brief and signal a subsequent stock market rebound.

"Tom Lee, head of research at Fundstrat, advised on CNBC's "Squawk Box" on Monday that it's crucial to monitor the VIX. He stated that when the VIX reaches its peak and begins to decline, the recovery can be just as swift."