About how many more percent of Amerians worked in services in 1980 than in 1955?
return Amerians ;return #1 that worked in   services ;return #2 in   1980 ;return #2 in   1955 ;return percent of #3 ;return percent of #4 ;return the  difference of #5 and  #6
['select', 'filter', 'filter', 'filter', 'project', 'project', 'arithmetic']