@Override
 public Object[][] getData(String sector, String keys, int t, String select) {
   final Object[][] result;
   final SectorDataset sectorDataset = getSectorDataset(sector, t);
   if (sectorDataset != null) {
     result = sectorDataset.getData(keys, select);
   } else {
     result = null;
   }
   return result;
 }