diff --git a/Lombiq.ChartJs.Samples/Controllers/SampleController.cs b/Lombiq.ChartJs.Samples/Controllers/SampleController.cs
index f2c39f9..f8646f5 100644
--- a/Lombiq.ChartJs.Samples/Controllers/SampleController.cs
+++ b/Lombiq.ChartJs.Samples/Controllers/SampleController.cs
@@ -121,7 +121,7 @@ public async Task<IActionResult> History(string incomeTag = null, string expense
         return View(new HistoryViewModel
         {
             Labels = transactions.Keys
-                .OrderBy(item => item)
+                .Order()
                 .Select(item => item.ToString("MMMM yyyy", CultureInfo.InvariantCulture)),
             // You can find more detailed description about dataset here:
             // https://www.chartjs.org/docs/2.9.4/charts/line.html#dataset-properties