The basket previously held euros and dollars in proportions of 0.40 and 0.60 respectively, and has been adjusted in line with the CBR's 2007 Monetary Policy Guidelines.
"The Bank of Russia is gradually increasing the euro's share in the bi-currency basket structure to smooth out intraday volatility of the ruble against the dollar and other foreign currencies of importance for Russia," the Central Bank said earlier.
The CBR introduced the bi-currency basket as a foreign exchange rate benchmark in February 1, 2005. The basket structure was initially 0.1 euros and 0.9 dollars.
In late December 2005, the bank changed the bi-currency basket structure to 0.4 euros and 0.6 dollars from 0.35 and 0.65 respectively.