Diana Lewis vgwn37a
 
  All flour is presifted but it settles during shipment. A cup of flour
  scooped directly from the bag can weigh up to 5 ounces. It SHOULD
  weigh 4 ounces. To measure correctly fluff up flour in the bag or
  canister. Then sprinkle it lightly with a spopon into a measuring
  cup, scrape the excess off the top with a knife. From King Arthur
  flour