For how many years was the ADF reduced in size, until it began growing again?
return the  ADF was  reduced in  size ;return the  ADF began growing again ;return years of #1 ;return year of #2 ;return the  lowest of #3 ;return the  difference of #4 and  #5
['select', 'select', 'project', 'project', 'aggregate', 'arithmetic']