The Hong Kong dollar is pegged to a tight band of between 7.75 and 7.85 versus the U.S. dollar.
The aggregate balance - the key gauge of cash in the banking system - will decrease to HK$123.336 billion on Sept. 29, an HKMA spokeswoman said on Wednesday.
($1 = 7.8498 Hong Kong dollars)
(Reporting by Donny Kwok; Editing by Muralikumar Anantharaman)