How many years was the time span where it is estimated that the total number of refugees is estimated between 700,000 and 1,200,000?
return years when  total number of refugees estimated  between 700,000 and  1,200,000 ;return lowest of #1 ;return highest of #1 ;return difference of #3 and  #2 ;return sum of #4 and  one
['select', 'aggregate', 'aggregate', 'arithmetic', 'aggregate']