Money is leaking out of banks in southern Europe as customers scoop deposits out of Greece, Spain and Italy to move cash to less indebted nations such as Germany.

Greece's total deposits plunged 28 percent from the peak in June 2009 to 169 billion euros ($225 billion) at the end of December, according to data compiled by Bloomberg. In Spain, deposits slid 5 percent in the five months through November to 934 billion euros, the least since April 2008. Italian banks held 974 billion euros in November, the lowest in 18 months.

Deposits in Germany have climbed by almost 10 percent since May 2010, when Greece was granted its first bailout. Deposits have risen every month except five since the end of 2009, and reached 2.15 trillion euros at the end of 2011, Bloomberg data show. The deteriorating growth outlook in the euro region risks exacerbating those flows, according to Dario Perkins, an economist at Lombard Street Research in London.