The CBOE Volatility Index (VIX), a measure of expected future fluctuations in the S&P 500 based on options prices, climbed back above the 20 level during early trading on Monday, reaching a high of 21.58. This follows the VIX closing at its lowest level last Friday since the outbreak of the Iran conflict in late February.

After the announcement of a two-week ceasefire agreement between the US and Iran on Tuesday evening, the VIX plummeted 18.4% to 21.04 last Wednesday, fell another 7.4% to 19.49 on Thursday, and declined a further 1.3% to 19.23 on Friday.

Since the conflict began, the VIX peaked at a closing level of 31.05 on March 27, having reached an intraday high of 31.65 on the same day.