How many percent higher was the per capita GDP in the 1970s than it was in the 1960s?
return per capita GDP ;return #1 in  the  1970s ;return #1 in  the  1960s ;return percent of #2 ;return percent of #3 ;return difference of #4 and  #5
['select', 'filter', 'filter', 'project', 'project', 'arithmetic']