Hong Kong’s de facto central bank stepped into the currency market twice within 12 hours, selling US$$1.74 billion ahead of an expected US interest rate rise on Thursday, to defend the local dollar against the weakening effects of capital outflow.

The Hong Kong Monetary Authority bought a total of HK$9.255 billion and sold US$1.179 billion early on Wednesday morning to bolster the exchange rate and return the currency to its trading band, after it briefly fell to HK$7.8500 per US dollar. The band, in place since 2005, allows the Hong Kong dollar to fluctuate between HK$7.7500 and HK$7.8500 against the American currency.

The intervention amount was the HKMA’s largest in seven such actions this year. It was also the second intervention in 12 hours after the HKMA bought a total of HK$4.396 billion and sold US$560 million on Tuesday night.