To put it bluntly: that decline is not chicken-feed! If the above rate continues, Greek banks will be totally out of deposits in another 63 months (some time in 2017).
But the real amazing thing is that there still are 170 BEUR in bank deposits! Greece has been in trouble for over 2 years by now but since the beginning of this year it has really been like flirting with disaster most of the time. The Euro-exit is officially being discussed as a possiblity. Greeks are publicly debating the pro’s/con’s of a Euro-exit. One would have thought that in such a climate, everyone would rush to the bank to withdraw Euro bank notes while they can still be withdrawn (and saved them under the blanket at home).
Obviously, the risk is not quite as big as it would normally be because the ECB has so far stood ready to provide all funding which Greek banks have needed. They will most likely continue to do that but will that continue to make Greek savers feel safe?
If a real run on deposits would start some time soon, I would not be surprised!