Foreign investors increased their holdings of onshore Chinese bonds by a record last month, as the debt posted the biggest advance in more than two years.

Overseas investors purchased net 66.4 billion yuan ($10.4 billion) of the securities in April to bring the total holdings to an unprecedented 1.15 trillion yuan, according to data from the China Central Depository & Clearing Co. That was the biggest increase ever for data going back to 2014, and more than triple the net purchase of 20.7 billion yuan the previous month.

Chinese bonds had their best returns since December 2015 last month as interbank liquidity improved and inflation concerns eased, while most other major markets saw losses as central banks prepared to unwind stimulus. Bloomberg LP’s announcement in late March to add China’s yuan-denominated bonds to the Bloomberg Barclays Global Aggregate Index has also drawn in foreign funds, according to Dariusz Kowalczyk, senior emerging-market strategist at Credit Agricole SA.

“We expect further large inflows in the medium- to long-run, averaging $120 billion per annum,” said Kowalczyk in Hong Kong. “This will put upward pressure on the yuan, which – after a likely short-term weakening – will resume appreciation in the second half.”

Economists expect the onshore yuan to weaken slightly to 6.39 per dollar in the fourth quarter from 6.3592 on Monday, according to data compiled by Bloomberg. Foreign investors boosted holdings of China’s bonds by 346 billion yuan last year to 1.2 trillion yuan and further expanded the position to 1.36 trillion yuan at the end of March, separate figures from the People’s Bank of China showed. That accounted for 1.8 percent of the nation’s 75.9 trillion yuan debt market.

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