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Beispiel wie es von Google übertragen wird:
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gtag("event", "purchase", {
    transaction_id: "T_12345",
    // Sum of (price * quantity) for all items.
    value: 72.05,
    tax: 3.60,
    shipping: 5.99,
    currency: "USD",
    coupon: "SUMMER_SALE",
    items: [
     {
      item_id: "SKU_12345",
      item_name: "Stan and Friends Tee",
      affiliation: "Google Merchandise Store",
      coupon: "SUMMER_FUN",
      discount: 2.22,
      index: 0,
      item_brand: "Google",
      item_category: "Apparel",
      item_category2: "Adult",
      item_category3: "Shirts",
      item_category4: "Crew",
      item_category5: "Short sleeve",
      item_list_id: "related_products",
      item_list_name: "Related Products",
      item_variant: "green",
      location_id: "ChIJIQBpAG2ahYAR_6128GcTUEo",
      price: 10.01,
      quantity: 3
    },
    {
      item_id: "SKU_12346",
      item_name: "Google Grey Women's Tee",
      affiliation: "Google Merchandise Store",
      coupon: "SUMMER_FUN",
      discount: 3.33,
      index: 1,
      item_brand: "Google",
      item_category: "Apparel",
      item_category2: "Adult",
      item_category3: "Shirts",
      item_category4: "Crew",
      item_category5: "Short sleeve",
      item_list_id: "related_products",
      item_list_name: "Related Products",
      item_variant: "gray",
      location_id: "ChIJIQBpAG2ahYAR_6128GcTUEo",
      price: 21.01,
      promotion_id: "P_12345",
      promotion_name: "Summer Sale",
      quantity: 2
    }]
});