Which group has a smaller percentage in Skojpe, the Serbs or the Roma?
return groups in  Skojpe ;return #1 that is the  Serbs ;return #1 that is the  Roma ;return percentage of #2 ;return percentage of #3 ;return which is lowest of #4 ,  #5
['select', 'filter', 'filter', 'project', 'project', 'comparison']