The US dollar continues to depreciate against the Bangladeshi currency taka although Bangladesh Bank, in its effort to keep the price of the dollar stable, purchased greenbacks worth $4.72 billion from the local banks in this fiscal year.The BB data showed that the dollar depreciated this week as it was quoted (buy-sales) at Tk 77.63-Tk 77.63 on Tuesday, at Tk 77.63-Tk 77.64 on Monday, at Tk 77.64-Tk 77.64 on Sunday and Tk 77.64-Tk 77.65 on Saturday.‘To avoid the depreciating trend in the dollar price, the central bank purchased dollar worth $365 million from the local scheduled banks in the first 20 days of this month, but its effort has virtually failed,’ a BB official told New Age on Wednesday.He said the depreciation of the dollar had already put a negative impact on the country’s export sector and the inward inflow of remittance.The dollar started to depreciate against the taka from February 26 this year after a steady run in the previous nine months as the demand for greenbacks declined significantly in the local market amid sluggish business due to political unrest.The BB data showed that the dollar was quoted at Tk 77.75-Tk 77.74 on February 26 from Tk 77.75-Tk 77.75 on February 25.The dollar might have declined more in the last few months if the central bank did not purchase the greenbacks from the market, the BB official said.The central bank purchased dollar worth $515 million in April, $480 million in March, $652 million in February and $295 million in January.The dollar price had risen to Tk 84.45 on January 29, 2012.From January 29, 2012 to May 30, 2013, the price of dollar against the taka continuously had declined.After the period, the BB was able to keep the dollar price stable as it had purchased huge amount of greenbacks, the BB official said.He said, ‘A number of scheduled banks are now keeping excess greenbacks as the country posted a satisfactory export growth against a lower import payments in recent months of the fiscal year 2013-2014.’For this reason, the BB purchased $4.72 billion from the local banks from July 1 to May 20 of the FY14 in bid to tackle the dollar depreciation against the taka, he said.The central bank also purchased greenbacks worth $4.53 billion in the FY13.After the BB had bought a huge amount of dollar last fiscal year, the taka remained stable at around 77.75 a dollar between May 2013 and February 2014.Following the fresh dollar purchase this fiscal year, the country’s foreign exchange reserve rose to a record $20-billion mark on April 10 for the first time.The foreign exchange reserve will increase more if the BB continues to purchase dollar in the months to come, the BB official said.He said the huge amount of foreign exchange reserve remained idle as the investment sector was still passing a stagnant situation.