Hedging is back as investors fret over concerns about everything from the US presidential election to second-quarter earnings, economic growth and interest rates.

The Cboe Volatility Index, a gauge of options prices, surged the most in more than a year last week as stocks sank with growing calls for Joseph Biden to quit the presidential race. Now that he’s done so and thrown US politics into uncharted territory, futures on the gauge have slipped after earlier climbing as much as 1.8% in Asian trading. October contracts, which measure swings around the vote, rose even more and were still up by 1:19 p.m. in Hong Kong.