EVEN by the boom-bust standards of China, the moves are incredible: gains as large as 19,267 percent in one trading session, and a near-complete wipeout in the next.

Welcome to the country’s options market, where outsized swings are par for the course and trading has never been more feverish. As volatility in Chinese stocks soars, some brave speculators are using options to magnify their bets.

Trading in options on the Shanghai-listed China 50 exchange-traded fund (ETF) soared to an all-time high Monday as the nation’s stock market posted its biggest single-day gain since August 2015.

Among the most active contracts was a call option expiring yesterday with a strike price of 2.8 yuan (42 U.S. cents). The option’s price soared 194-fold Monday as a 7.6 percent jump in the ETF increased the odds of the derivative expiring in the money. By the end of Tuesday, a 3.1 percent slump in the ETF had all but wiped out the option’s gain.

While there’s nothing unique to China about options experiencing huge swings when their underlying assets turn volatile close to expiry, recent moves in the stock market stand out.

Volatility in China’s benchmark equity index over the past 10 days has soared to the highest level among major markets worldwide, with price swings about five times bigger than those of the S&P 500 Index. (SD-Agencies)