Greece has spent 3% of gdp more than they should have done on defence for the last 24 years at least. In that period, since 1988, Greek GDP has grown from $80bn to $300bn and still spending has kept pace!
See here Greek spending as a % of GDP since 1988 –graph
See here Greek GDP growth since 1988 – graph
If Greek spending on defence had been 3% lower then well over 50% of Greek debt would not exist.