Bangladesh Bank bought $5.15 billion from the foreign exchange market last fiscal year to shore up the country's exchange rate.
If the exchange rate falls much, the exporters and remitters are acutely affected, which prompts the central bank to buy a huge amount of dollars, said a BB official, adding that BB bought $4.53 billion in fiscal 2012-13.
The dollar against the taka in the interbank market stood at Tk 77.63 on July 8, which was Tk 77.75 a year ago.
Foreign exchange reserves on June 16 crossed the $21 billion-mark for the first time in the nation's history, helped by exports and remittances, said Kazi Saidur Rahman, general manager of BB.
The figure sank below $21 billion at the beginning of the month after paying dues to the Asian Clearing Union. The figure crossed the $21 billion-mark again yesterday and stood at $21.12 billion.