How many more people lived in Peloponnese pre-war compared to the population after the war?
return Peloponnese ;return people of #1 ;return #2 pre-war ;return #2 after the  war ;return number of  #3 ;return number of  #4 ;return difference of #5 and  #6
['select', 'project', 'filter', 'filter', 'aggregate', 'aggregate', 'arithmetic']