(Bloomberg) -- Leaders of China’s provinces have less job security than at any time in the past four decades, a sign of the upheaval caused by President Xi Jinping’s anti-corruption campaign.

The ruling Communist Party’s provincial heads stayed in the job just 1.6 years on average in 2021, according to data compiled by Cheng Li, director of the John L. Thornton China Center at the Brookings Institution, a U.S. research organization.

That was the shortest average duration for a post that carries a five-year term in Li’s data going back to 1985, when party bosses held their jobs for 4.5 years. Tenures have been dropping for decades but the phenomenon has sped up amid Xi’s curbs on graft, Li wrote in an article.

That campaign to clean up the government of the world’s No. 2 economy has had the added benefit of removing potential political rivals as Xi prepares to secure a precedent-defying third term in office at twice-a-decade leadership congress later this year. Lower officials around the nation will also be jockeying for promotions before that event.

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Xi signaled in 2013, shortly after taking power, that he wouldn’t spare any dirty official, and millions of cadres at all levels of government have been busted. One of the earliest victims of the anti-corruption purge was Zhou Yongkang, who had been one of the nine most senior politicians in China. He was sent to prison for life for bribery, abuse of power and leaking state secrets -- a takedown that smashed taboos about who was untouchable in elite Chinese politics. 

Xi has kept up the pressure on Chinese officials since then. Last year, Sun Lijun, a former vice minister of public security, was expelled from the party for “cultivating personal power and forming an interest group,” a sign that Xi remains keen to tame rivals.

Li also wrote that mayors and governors, who answer to provincial party bosses, also face greater turnover in their roles. They lasted just 0.8 years in office in 2021, down from 2.5 in 1985, according to his March 27 article, which used sources including the website of the official Xinhua News Agency.   

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