The European Central Bank said that its interest income earned from Greek bonds last year helped boost its 2012 net profit by more than a third.

The eurozone central bank for the first time provided a breakdown of the bonds held by eurozone central banks under the Securities Markets Program, or SMP-the bond-buying plan it launched in 2010 to reduce the borrowing costs of struggling eurozone governments-offering a window into how much the ECB has profited from its rescue efforts throughout the region's debt crisis.