diff --git a/stores/data.js b/stores/data.js
index 41c7753..cb9ee8f 100644
--- a/stores/data.js
+++ b/stores/data.js
@@ -903,14 +903,36 @@ export const useDataStore = defineStore('data', () => {
                     label: "Einkaufspreis",
                     component: purchasePrice,
                     inputType: "number",
-                    inputTrailing: "EUR"
+                    inputTrailing: "EUR",
+                    inputChangeFunction: function (row) {
+                        if(row.markupPercentage) {
+                            row.sellingPrice = row.purchasePrice * (1+row.markupPercentage/100);
+                        } else {
+                            row.sellingPrice = row.purchasePrice;
+                        }
+                    }
+                },{
+                    key: "markupPercentage",
+                    label: "Aufschlag",
+                    inputType: "number",
+                    inputTrailing: "%",
+                    inputChangeFunction: function (row) {
+                        if(row.sellingPrice) {
+                            row.sellingPrice = row.purchasePrice * (1+row.markupPercentage/100);
+                        }
+                    }
                 },{
                     key: "sellingPrice",
                     label: "Verkaufpreispreis",
                     required: true,
                     component: sellingPrice,
                     inputType: "number",
-                    inputTrailing: "EUR"
+                    inputTrailing: "EUR",
+                    inputChangeFunction: function (row) {
+                        if(row.markupPercentage) {
+                            row.purchasePrice = (row.sellingPrice / (1+row.markupPercentage/100)).toFixed(4);
+                        }
+                    }
                 },{
                     key: "taxPercentage",
                     label: "Umsatzsteuer",