How many percentage points, in April 2010, higher was the unemployment rate in the U.S. than in Japan in 2012?
return the  U.S. ;return unemployment rate of #1 ;return #2 in   April 2010 ;return Japan ;return unemployment rate of #4 ;return #5 in   2012 ;return percentage of #3 ;return percentage of #6 ;return difference of #7 and  #8
['select', 'project', 'filter', 'select', 'project', 'filter', 'project', 'project', 'arithmetic']