How many more dollars was Frederick W. Smith's  base salary  in 2008 than 2009?
return Frederick W. Smith ;return base salary of #1 ;return #2 in  2008 ;return #2 in  2009 ;return dollars of #3 ;return dollars of #4 ;return number of  #5 ;return number of  #6 ;return difference of #7 and  #8
['select', 'project', 'filter', 'filter', 'project', 'project', 'aggregate', 'aggregate', 'arithmetic']