 This was an attempt to push down the value of the yen against the US dollar to stimulate the domestic economy by making Japanese exports cheaper; however, it was ineffective.On 4 August 2011 the BOJ announced a unilateral move to increase the commercial bank current account balance from ¥40 trillion (US$504 billion) to a total of ¥50 trillion (US$630 billion).In October 2011, the Bank expanded its asset purchase program by ¥5 trillion ($66bn) to a total of ¥55 trillion.