Russian Central Bank Governor Elvira Nabiullina presents the new 200 rouble banknote in Moscow, Russia October 12, 2017. REUTERS/Grigory Dukor 

Russian Central Bank Governor Elvira Nabiullina reacts while presenting the new 200 and 2,000 rouble banknotes in Moscow, Russia October 12, 2017. REUTERS/Grigory Dukor 

Russian Central Bank Governor Elvira Nabiullina presents the new 2,000 rouble banknote in Moscow, Russia October 12, 2017. REUTERS/Grigory Dukor 

Russian Central Bank Governor Elvira Nabiullina speaks during the presentation of the new 200 and 2,000 rouble banknotes in Moscow, Russia October 12, 2017. REUTERS/Grigory Dukor 

Russian Central Bank Governor Elvira Nabiullina speaks during the presentation of the new 200 and 2,000 rouble banknotes in Moscow, Russia October 12, 2017. REUTERS/Grigory Dukor 

Russian Central Bank Governor Elvira Nabiullina speaks during the presentation of the new 200 and 2,000 rouble banknotes in Moscow, Russia October 12, 2017. REUTERS/Grigory Dukor 

Russian Central Bank Governor Elvira Nabiullina presents the new 2,000 rouble banknote in Moscow, Russia October 12, 2017. REUTERS/Grigory Dukor 

Russian Central Bank Governor Elvira Nabiullina presents the new 200 rouble banknote in Moscow, Russia October 12, 2017. REUTERS/Grigory Dukor 

Russian Central Bank Governor Elvira Nabiullina presents the new 2,000 Russian rouble banknote in Moscow, Russia October 12, 2017. REUTERS/Grigory Dukor 

Russia's Central Bank Governor Elvira Nabiullina exits a car as she arrives for a meeting of Russian President Vladimir Putin with his Moldovan counterpart Igor Dodon in Sochi, Russia October 10, 2017. REUTERS/Maxim Shemetov 

Russian Central Bank's First Deputy Governor Ksenia Yudayeva attends an interview at the Reuters Russia Investment summit in Moscow, Russia September 18, 2017. Picture taken September 18, 2017. REUTERS/Grigory Dukor 

Russian Central Bank's First Deputy Governor Ksenia Yudayeva attends an interview at the Reuters Russia Investment summit in Moscow, Russia September 18, 2017. Picture taken September 18, 2017. REUTERS/Grigory Dukor 

Russian Central Bank's First Deputy Governor Ksenia Yudayeva attends an interview at the Reuters Russia Investment summit in Moscow, Russia September 18, 2017. Picture taken September 18, 2017. REUTERS/Grigory Dukor 

Russian Central Bank's First Deputy Governor Ksenia Yudayeva attends an interview at the Reuters Russia Investment summit in Moscow, Russia September 18, 2017. Picture taken September 18, 2017. REUTERS/Grigory Dukor 

Russian Central Bank's First Deputy Governor Ksenia Yudayeva attends an interview at the Reuters Russia Investment summit in Moscow, Russia September 18, 2017. Picture taken September 18, 2017. REUTERS/Grigory Dukor 

Russian Central Bank's First Deputy Governor Ksenia Yudayeva attends an interview at the Reuters Russia Investment summit in Moscow, Russia September 18, 2017. Picture taken September 18, 2017. REUTERS/Grigory Dukor 

Russian Central Bank's First Deputy Governor Ksenia Yudayeva attends an interview at the Reuters Russia Investment summit in Moscow, Russia September 18, 2017. Picture taken September 18, 2017. REUTERS/Grigory Dukor 

RUSSIA-BANKS/ - Balace in the Russian banking sector changed in July-August, forcing the central bank to rescue two lenders from the Top-20 list. 

A man walks out of the Russia's B&N Bank headquarters in central Moscow, Russia September 20, 2017. REUTERS/Grigory Dukor 

People gather outside the Russia's B&N Bank headquarters in central Moscow, Russia September 20, 2017. REUTERS/Grigory Dukor 

A man walks down the stairs at the Russia's B&N Bank headquarters in central Moscow, Russia September 20, 2017. REUTERS/Grigory Dukor 

Russian central bank governor Elvira Nabiullina speaks during a news conference in Moscow, Russia September 15, 2017. REUTERS/Sergei Karpukhin 

Russian central bank governor Elvira Nabiullina attends a news conference in Moscow, Russia September 15, 2017. REUTERS/Sergei Karpukhin 

Russian central bank governor Elvira Nabiullina speaks during a news conference in Moscow, Russia September 15, 2017. REUTERS/Sergei Karpukhin 

Russian central bank governor Elvira Nabiullina speaks during a news conference in Moscow, Russia September 15, 2017. REUTERS/Sergei Karpukhin 

Russian central bank governor Elvira Nabiullina attends a news conference in Moscow, Russia September 15, 2017. REUTERS/Sergei Karpukhin 

Russian central bank governor Elvira Nabiullina gestures during a news conference in Moscow, Russia September 15, 2017. REUTERS/Sergei Karpukhin 

Russian central bank governor Elvira Nabiullina speaks during a news conference in Moscow, Russia September 15, 2017. REUTERS/Sergei Karpukhin 

Russian central bank governor Elvira Nabiullina gestures during a news conference in Moscow, Russia September 15, 2017. REUTERS/Sergei Karpukhin 

Russian central bank governor Elvira Nabiullina speaks during a news conference in Moscow, Russia September 15, 2017. REUTERS/Sergei Karpukhin 

Alexander Morozov, director of research and forecasting department of Russia's central bank, poses during an interview with Reuters at the 26th International Financial Congress in St. Petersburg, Russia, July 12, 2017. Picture taken July 12, 2017. REUTERS/Elena Fabrichnaya 

Russian central bank governor Elvira Nabiullina speaks during a news conference in Moscow, Russia, June 16, 2017. REUTERS/Sergei Karpukhin 

Russian central bank governor Elvira Nabiullina attends a news conference in Moscow, Russia, June 16, 2017. REUTERS/Sergei Karpukhin 

Russian central bank governor Elvira Nabiullina gestures during a news conference in Moscow, Russia, June 16, 2017. REUTERS/Sergei Karpukhin 

Russian central bank governor Elvira Nabiullina reacts during a news conference in Moscow, Russia, June 16, 2017. REUTERS/Sergei Karpukhin 

Russian central bank governor Elvira Nabiullina speaks during a news conference in Moscow, Russia, June 16, 2017. REUTERS/Sergei Karpukhin 

Russian central bank governor Elvira Nabiullina attends a news conference in Moscow, Russia, June 16, 2017. REUTERS/Sergei Karpukhin 

Russian central bank governor Elvira Nabiullina takes her seat during a news conference in Moscow, Russia, June 16, 2017. REUTERS/Sergei Karpukhin 

Igor Dmitriev, the head of the monetary policy department at the Bank of Russia, speaks during an interview with Reuters in Moscow, Russia, June 2, 2017. Picture taken June 2, 2017. REUTERS/Maxim Shemetov 

Igor Dmitriev, the head of the monetary policy department at the Bank of Russia, gestures during an interview with Reuters in Moscow, Russia, June 2, 2017. Picture taken June 2, 2017. REUTERS/Maxim Shemetov 

Igor Dmitriev, the head of the monetary policy department at the Bank of Russia, speaks during an interview with Reuters in Moscow, Russia, June 2, 2017. Picture taken June 2, 2017. REUTERS/Maxim Shemetov 

Igor Dmitriev, the head of the monetary policy department at the Bank of Russia, speaks during an interview with Reuters in Moscow, Russia, June 2, 2017. Picture taken June 2, 2017. REUTERS/Maxim Shemetov 

Russian Central Bank Governor Elvira Nabiullina reacts during a session of the St. Petersburg International Economic Forum (SPIEF), Russia, June 1, 2017. REUTERS/Sergei Karpukhin 

Russian central bank Governor Elvira Nabiullina attends a news conference in Moscow, Russia March 24, 2017. REUTERS/Maxim Shemetov 

Russian central bank Governor Elvira Nabiullina attends a news conference in Moscow, Russia March 24, 2017. REUTERS/Maxim Shemetov 

Russian central bank Governor Elvira Nabiullina speaks during a news conference in Moscow, Russia March 24, 2017. REUTERS/Maxim Shemetov 

Russian central bank Governor Elvira Nabiullina arrives for a news conference in Moscow, Russia March 24, 2017. REUTERS/Maxim Shemetov 

As the Russian rouble strikes a balance after more than two years of jittery free float, the Russian central bank unexpectedly boosts the rouble volatility again by agreeing to start buying dollars for the country’s depleted reserves. 

Russia's Central Bank Governor Elvira Nabiullina attends the congress of the Russian Union of Industrialists and Entrepreneurs (RSPP) in Moscow, Russia, December 19, 2016. REUTERS/Maxim Shemetov 

Russia's First Deputy Prime Minister Igor Shuvalov (L) and Central Bank Governor Elvira Nabiullina attend the congress of the Russian Union of Industrialists and Entrepreneurs (RSPP) in Moscow, Russia, December 19, 2016. REUTERS/Maxim Shemetov 

Russian central bank governor Elvira Nabiullina reacts during a news conference in Moscow, Russia, December 16, 2016. REUTERS/Maxim Shemetov 

Russian central bank governor Elvira Nabiullina gestures during a news conference in Moscow, Russia, December 16, 2016. REUTERS/Maxim Shemetov 

Russian central bank governor Elvira Nabiullina gestures during a news conference in Moscow, Russia, December 16, 2016. REUTERS/Maxim Shemetov 

Russian central bank governor Elvira Nabiullina reacts during a news conference in Moscow, Russia, December 16, 2016. REUTERS/Maxim Shemetov 

Russian central bank governor Elvira Nabiullina attends a news conference in Moscow, Russia, December 16, 2016. REUTERS/Maxim Shemetov 

Russian central bank governor Elvira Nabiullina attends a news conference in Moscow, Russia, December 16, 2016. REUTERS/Maxim Shemetov 

Russian central bank governor Elvira Nabiullina attends a news conference in Moscow, Russia, December 16, 2016. REUTERS/Maxim Shemetov 

A board, which reads 'Bank', is on display during sunset in central Moscow, Russia, November 21, 2016. REUTERS/Maxim Shemetov 

A visitor takes a picture of a commemorative Russian rouble coin from the collection of the museum and exhibition fund of the Central Bank at its headquarters in Moscow, Russia, October 1, 2016. REUTERS/Maxim Zmeyev 

Visitors observe commemorative Russian rouble coins from the collection of the museum and exhibition fund of the Central Bank at its headquarters in Moscow, Russia, October 1, 2016. REUTERS/Maxim Zmeyev