diff --git a/packages/victory-core/src/victory-util/data.ts b/packages/victory-core/src/victory-util/data.ts
index 6a207154c..f64540836 100644
--- a/packages/victory-core/src/victory-util/data.ts
+++ b/packages/victory-core/src/victory-util/data.ts
@@ -282,34 +282,44 @@ export function formatData(
 
   const data = preformattedData
     ? dataset
-    : dataset.reduce((dataArr, datum, index) => {
-        // eslint-disable-line complexity
-        const parsedDatum = parseDatum(datum);
-        const fallbackValues = { x: index, y: parsedDatum };
-        const processedValues = expectedKeys!.reduce((memo, type) => {
-          const processedValue = accessor[type](parsedDatum);
-          const value =
-            processedValue !== undefined
-              ? processedValue
-              : fallbackValues[type];
-          if (value !== undefined) {
-            if (typeof value === "string" && stringMap[type]) {
-              memo[`${type}Name`] = value;
-              memo[`_${type}`] = stringMap[type][value];
-            } else {
-              memo[`_${type}`] = value;
+    : sortData(dataset, props.sortKey, props.sortOrder).reduce(
+        (dataArr, datum, index) => {
+          // eslint-disable-line complexity
+          const parsedDatum = parseDatum(datum);
+          const fallbackValues = { x: index, y: parsedDatum };
+          const processedValues = expectedKeys!.reduce((memo, type) => {
+            const processedValue = accessor[type](parsedDatum);
+            const value =
+              processedValue !== undefined
+                ? processedValue
+                : fallbackValues[type];
+            if (value !== undefined) {
+              if (typeof value === "string" && stringMap[type]) {
+                memo[`${type}Name`] = value;
+                memo[`_${type}`] = stringMap[type][value];
+              } else if (type === "x" && props.sortKey) {
+                memo[`${type}Name`] = value.toString();
+                memo[`_${type}`] = index + 1;
+              } else {
+                memo[`_${type}`] = value;
+              }
             }
+            return memo;
+          }, {});
+
+          const formattedDatum = Object.assign(
+            {},
+            processedValues,
+            parsedDatum,
+          );
+          if (!isEmpty(formattedDatum)) {
+            dataArr.push(formattedDatum);
           }
-          return memo;
-        }, {});
 
-        const formattedDatum = Object.assign({}, processedValues, parsedDatum);
-        if (!isEmpty(formattedDatum)) {
-          dataArr.push(formattedDatum);
-        }
-
-        return dataArr;
-      }, []);
+          return dataArr;
+        },
+        [],
+      );
 
   const sortedData = sortData(data, props.sortKey, props.sortOrder);
   const cleanedData = cleanData(sortedData, props);