How many more lives were lost in the 1998 flood than in the 2004 floods?
return the  1998 flood ;return the  2004 floods ;return lost lives of #1 ;return lost lives of #2 ;return number of  #3 ;return number of  #4 ;return the  difference of #5 and  #6
['select', 'select', 'project', 'project', 'aggregate', 'aggregate', 'arithmetic']