How many more people, in terms of percentage, were in the 2nd and 3rd largest age groups combined compared to the largest?
return age groups ;return percentages of people of  #1 ;return the  largest  of #2 ;return the  2nd largest  of #2 ;return the  3rd largest  of #2 ;return sum of #4 and  #5 ;return the  difference of #6 and  #3
['select', 'project', 'aggregate', 'aggregate', 'aggregate', 'arithmetic', 'arithmetic']