How many more wins did the Tigers have in 1991 than in 1989?
return the  Tigers ;return wins in  1991 of #1 ;return wins in  1989 of #1 ;return number of  #2 ;return number of  #3 ;return the  difference of #4 and  #5
['select', 'project', 'project', 'aggregate', 'aggregate', 'arithmetic']