The Hong Kong dollar is pegged to a tight band of between 7.75 and 7.85 versus the US dollar.
The HKMA intervened twice on Thursday and once on Friday.
The aggregate balance, the key gauge of cash in the banking system, will decrease to $325.894 billion on Tuesday, a HKMA spokeswoman said on Saturday.
It dropped to around $50 billion in 2019 after the last series of HKMA interventions to stop the currency weakening. (Reuters)